Brian Clegg's Blog, page 128

Psst - want to borrow an ebook?

Whether you are an author or a reader, ebooks have taken a bit of getting used to. But there is no doubt after years of posturing about the death of paper books that ebooks have finally taken off. It has been interesting to hear politician Margaret Hodge in her campaign to avoid using corporate tax dodgers like Starbucks, Amazon and Google that she has said that she loves her Kindle and is finding it a real pain going back to paper books.
Lovely ebooks! Borrow your ebooks 'ere!
Rip off an author!
I am not the kind of person who throws my hands in the air and bewails the coming of the ebook, nor one who forecasts the demise of paper books any time soon. Bear in mind 25% of the UK population doesn't even use the internet - I suspect a significantly higher percentage will resist ebooks for a good number of years to come (though admittedly some technophobes will not be enthusiastic readers). But I do think we need to keep an eye on the pros and cons of ebooks.
One aspect that has come to my eye recently is the facility called Overdrive that allows you to borrow ebooks from libraries.
At the moment (from my library, at least) the facility is fairly limited. It provides a small selection from popular authors, but mostly its pretty obscure stuff. However it won't necessarily stay that way. We could in principle see every ebook in existence available for borrowing this way. And what happens to the author's income then?
In the UK and a number of other European countries (but not in the US) there is a facility called PLR. This provides a small payment for the author (currently around 6p in the UK) when a book is borrowed, or rather it is based on the scaling up of borrowings from a number of sample libraries. It's not something that will make you rich. I just got my Irish PLR and it amounted to £6.50 for the year. But the point is that you are being paid for the use of your books.
The danger with ebook lending is that it is much closer in nature to buying ebooks than conventional library lending is to buying paper books. With an ebook you don't really care that you don't have anything to treasure and own, and unlike a library book it will be no more battered after its 1,000th loan. It could mean a whole lot fewer people buying ebooks. So if it is allowed, there need to be a number of restrictions.
One is that you can't lend the same ebook to many people at once - it should be (and the system allows it to be) a check-out/check-in resource. It is also possible that ebooks for loan should cost a lot more than for purchase. This isn't impossible - the same has always applied to videos/DVDs, where a loan copy cost the hire shop or library much more than buying a personal copy for yourself. And the final essential is that ebook lending is taken into PLR. And here we have a problem.
The UK government agreed in the Digital Economy Act 2010 that PLR could be extended to audiobooks and ebooks, and that audiobooks and ebooks counted legally as books for PLR purposes. But it has since announced that 'It will not be extending PLR at this time' and so PLR 'remains restricted to books which are printed and bound.' This is ludicrous and arbitrary. So it's time the government got its finger out and caught up. Otherwise ebook lending should be disallowed until they can get their act together.

Don't (always) make it your own

TV singing shows like the X-Factor are infamous for their repeated use of nauseous clichéd phrases like 'It has been a rollercoaster' or 'You have been on such a journey.' (Pause to cringe.) But one such phrase that hasn't had the attention it deserves is 'You have made that song your own.'

This is a feature of the age of recording stars. In the olden days, if a song was ascribed to anyone (and many weren't) it was the composer. Now, though, it's the performer. When competitors are asked what they are going to perform they don't say 'New York,' (say) they say 'New York by Alicia Keys,' not meaning she wrote it, but that she recorded it. So making a song your own is essentially about singing a song someone else has recorded, but putting your own mark on it so it doesn't sound like their recording, something this year's X-Factor finalists were particularly strong on.

That's all very well in the context of the show. If you do, say, a Michael Jackson song and do it purely in the style of Michael Jackson, you are an impersonator, not a performer in your own right. But the trouble is when you apply the same logic to music that doesn't have the taint of pre-ownership. And this is where things went horribly wrong when the X-Factor finalists sang Silent Night when the Downing Street Christmas tree was switched on. If you haven't seen it, and have a strong stomach, you can hear it at around the 42 second mark in the video below.



Oh dear. Each of the three tried very hard to make 'Silent Night' their own. And thoroughly ruined it. This is because with most decent music, what is important is the music, not how clever you can be in your rendition of it. If, for instance, you listen to different recordings of Beethoven piano sonatas or Byrd motets you will hear subtle differences of interpretation. But it is the music itself that shines through. The performer is secondary to the music. And these sad little people thought it ought to be the other way round.

I'm not saying Silent Night is a great piece of music. It is a simple tune written to be sung simply. But by attempting to make it their own, those three murdered it. Excruciating is probably the best word. Surely someone in the X-Factor production team could realise this. You can almost see David Cameron's blood curdle - just look at his expression in the starting still on the YouTube video above. Whether or not you support his politics, it's not fair that our Prime Minister had to suffer this. X-Factor - you should be ashamed of yourself. Learn a bit more about music, and a little less about showing off, please.

I'm Dreaming of a Green Christmas?

I've always had a lot of time for the Centre for Alternative Technology in the heart of Wales. Okay, the hippyish feel of the place isn't really me, but when I was writing Ecologic it proved a very helpful resource, and though they may be evangelical about being green, they don't go about it with a big stick like some of the green lobby.

For that reason I was rather taken with a press release they sent out on having a green Christmas. I am going to pass on that festive-but-caring message, though I will be throwing in one or two of my own comments as I go. So here we go. From now on the CAT gets the ordinary text and my comments are italic:


Christmas is a time for excesses and whilst its [sic] wonderful to kick back and relax with family and friends there are lots of things we can do to make Christmastime more sustainable and reduce our environmental impact. “ From reducing the amount of rubbish we produce, making our own Christmas decorations to buying ethically sourced and traded Christmas gifts there are loads of things we can do to make Christmas more sustainable.”

While I could quibble about their ability to punctuate (and what are those inverted commas for, guys?) - a perfectly sensible sentiment.
Buy ethically traded gifts, shops such as CAT's eco store offer a wide range of products, specially selected for their low environmental impact and eco- credentials. >> You may be thinking 'There's a time for composting toilets, but I don't want to find one under the Christmas tree, there are some rather entertaining gifts here (bamboo socks, anyone?) including some made from PLASTIC! I emphasise this merely to highlight that they are properly green, not knee-jerk green.Give someone a course, CAT short courses make the perfect present for family and friends to learn about more sustainable ways of living and allowing them to put those ideas into practice. >> Sorry, I really can't go for this one. Courses don't make a perfect present, they are very disappointing gifts. Don't do it, unless either a) you don't like the recipient or b) you know the recipients are really worthy people, the sort that like yurts.Reduce the millions of Christmas trees ending up in landfill sites. The alternatives are to get a tree with roots so it can be potted and reused next year, ensure that your local council will recycle dead trees (many councils grind them down into chips to be used as mulch in parks or gardens) or be creative: use branches, paint and cardboard. >> While the last suggestion is a joke - please don't do it - I do strongly encourage you to go for a rooted tree or to recycle. Our council takes them away: jolly convenient. The only thing with the rooted tree, if you put it in the ground after Christmas, leave it there and get another. Don't disturb it again, you risk killing it.Reuse your Christmas decorations. Bring out your old decorations rather than buying new ones every year, turn scratched CDs into personalised decorations, create decorations out of fruit and popcorn which can be fed to hungry birds in the new year. >> Ah, the Blue Peter spirit. Actually I don't think many of us need much encouraging to bring out old Christmas decorations. It's part of the delight of the season. By all means get one or two new ones (we need to support the economy) but don't go mad. For me, the only reason for using DIY decorations is because your children made them, so you can go 'Ahh!' Otherwise avoid like the plague unless you are really artistic. Trust me on this.Recycle Christmas cards and wrapping paper. Many charity shops sell gummed labels to stick over previous messages and addresses and E-cards are an eco alternative to paper based cards. Be creative when wrapping presents use fabric, magazine pages, aluminium foil that can be reused for cooking, to create beautiful, unique wrapping paper. >> A hearty 'Yes!' to the be creative bit. I've seen some brilliant gift bags, for instance, made from scraps of old wallpaper, sewn up and given a string handle. (Not sure about magazine pages, though.) By all means recycle cards and wrapping paper, but reusing them is just a bit... tacky.Reduce the number of polluting food miles your festive meals clock up by buying locally grown or reared produce. Locally produced, organic food tends to taste better too! For those Christmastime essentials from faraway places i.e. chocolate and coffee - make sure you buy Fairtrade products. >> Mixed feelings about this one. Yes to buy local. We get our turkey from a local farmer, and it's brilliant. And fresh local food may well taste better. It has been clearly established that organic food does NOT taste any better, and I try not to buy it myself as I don't approve of many things the Soil Association does. But their animal welfare standards are good. Our turkey is free range but not organic, and that's what I'd go for. Fair trade is fine, but don't think this is limited to the 'Fairtrade' label - that is a marketing organization. Recycle your scraps. Turn your vegetable peelings, fruit cores and nutshells into fertile compost and avoid unnecessarily using landfill sites. If you avoid composting cooked food, you will not attract unwanted wildlife and it won't smell. Many local authorities provide free c >> That's not me editing them, the original stopped like this. If your council does food recycling (some do) I'm all for it, but if it's DIY, do make sure that you avoid attracting rats etc. - they don't just go for cooked food - by making sure your composting is done in a closed, robust bin, rather than an open compost heap. Most of all, enjoy it! Don't feel guilty about not always being green in your Christmas celebrations. It's always a balance. But if you can have fun and be green too, why not? All together now: 'I'm dreaming of a green Christmas, just like the ones we never knew...'

Tread lightly on the fossil record

The view from my Southend hotel room on Wednesday morningOn Tuesday and Wednesday I spent two days in Southend, giving talks at the High School for Boys. Perhaps as karmic revenge for my referring to the town as 'sunny Southend' I woke up on Wednesday to a surprise snowfall, which was rather fun.

The talks went well (I think) but a useful bonus was a chance to attend a little symposium the school was running for a group of students. Said students were entering a competition to write a piece about science and religion, so the school put together a panel of five of their teachers, who each gave their personal opinion on science v religion, from an out-and-out atheist perspective to one that put the two on very much equal footing and could see no conflict between them.

The students were then given the chance to ask questions of the teachers. One, rather daringly, questioned a statement from the head teacher that while he had no problem with evolution, we need to recognize that as a theory it has some big problems. Would the head like to identify one of these problems, asked the bold student.

The head responded that the fossil record does not provide good evidence for evolution.  Not that it counters evolution, but is not sufficient to support it. With the thoughts of what my friend Henry Gee would say, who gets rather hot under the collar when the fossil record is waved around in a dangerous fashion, I waded in and pointed out that the fossil record is inherently incomplete in a big way, and any attempt to use it to cast doubt on evolution was dubious at best.

Ah yes, said the head, but the fact remains that there are not, for example, enough dead-end fossils. We should expect many more fossils of creatures that were evolutionary errors, the outcome of random variation gone wrong.

A breakfast view that morningNow this, I admit, is where I chickened out. Bear in mind that this was the head of the school that was employing me and (I hope!) may do so again in the future. So rather than come back on that remark, I let it lie. (I also thought it was wrong to hog the debate, when it was supposed to be for the students to ask questions.)

However, it's not going to stop me responding now. I know very little of palaeontology and the likes of Dr Gee are welcome to correct me on this, but my response would have been 'So what?' I'm not at all surprised there aren't many dead-ends for three reasons. One is that by definition many dead-ends would be, well dead-ends. They'd be one-offs. Chances of being fossilized? Vanishingly small.

Then what I always feel is the most amazing aspect of evolution, something that isn't made enough of. This is that every individual creature throughout history has been the same species as its parent. Even though if you follow back through our parental history you will eventually get back to bacteria-like ancestors, you will never see a species change from one generation to the next. It's a glorious paradox. So inevitably the first step down a dead-end will be indistinguishable from a non dead-end fossil.

Finally, I very much doubt how well we can deduce whether or not many fossils are dead-ends, bearing in mind what a fossil is. There may be some where it's pretty obvious but surely there will be many where it won't. To use a breeding rather than evolutionary analogy, I doubt if anyone looking at a fossilized mule would say 'that's a dead-end animal. It won't continue the line.' But the fact is a mule is just that.

As for the religion v science debate it was inevitably open ended. But it was fun trying and much kudos to the school for trying it.

A little brain work

I'm just about to catch a train to sunny Southend for a couple of days of talks, but before I go, I'll leave you with a little brain stretching challenge.


I have two bottles, one containing water and the other containing wine. I pour one measure of wine into the water bottle. I then pour an equal measure from the water bottle back into the wine bottle. At the end, there is just as much water in the wine as there is wine in the water. Which of the following have to be true to make this possible (you can choose more than one):

The bottles are the same sizeThe water and wine are thoroughly mixed after the measure is poured into the water bottle.The wine and water have to be thoroughly mixed after the measure is poured back into the wine bottleThe wine has the same density as the waterThe water and wine are miscible

… or is it impossible to be certain that there is just as much water in the wine as there is wine in the water?

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Don't go any further until you've attempted some sort of answer.

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Last chance to consider your answer.

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In fact, none of the conditions have to hold true - there will always be just as much wine in the water as water in the wine. Think of it like this: at the end of the process, the wine bottle holds exactly the same amount as it did initially, so it must have had exactly the same amount of water added to it as wine was removed.

Notice how the way that the question was phrased can distract you from the true facts. Even if you got the right answer, the chances are that the phrasing proved a distraction. You probably worried about partial mixing of water and wine, for example. Sometimes re-phrasing the question is an essential for knowledge gathering and creativity.

The Christmas Music dilemma

I was on BBC Wiltshire with the excellent Mark O'Donnell on Saturday, and a topic of discussion was whether to play a Christmas song or a winter song (as it was a bit early for Christmas stuff). What was interesting in this discussion, as so often is the case, was the hinterland.

There was significant debate over whether a song that doesn't mention Christmas, or Christmas specific appurtenances like Santa Claus and Rudolph, but that is traditionally associated with Christmas is a Christmas song or a winter song. Think Frosty the Snowman, Let it Snow or Winter Wonderland. Okay, we're in 'how many angels can dance on the head of a pin' territory, but hey, it's December.

Personally I was strongly in favour of letting these through as winter songs. But it led me to think of another Christmas music dilemma. I'm a great fan of church music, both singing it and listening to it - and I love carols. Now, technically we are currently in Advent, the season leading up to Christmas - the equivalent of Lent before Easter. And there is plenty of good Advent music. So there is an argument that you should only sing Advent music until Christmas begins at midnight on 24 December. But...

But, I think most people would agree, that Christmas carols seem limp and out of place after around 26 December. It would be ridiculous to limit ourselves to singing and hearing these brilliant bits of music to one day. So reluctantly I have to say, I think it's okay to go with the carols from the start of December. Ding Dong away, folks. Ding Dong away.

Just in case you think all carols are crass, here's an example of a high class Christmas carol - Peter Warlock's Bethlehem Down. Nice story too. Warlock (real name Philip Heseltine) and his friend Bruce Blunt wanted to get drunk over Christmas. They had no cash, so they ran off this little number to pay for the festivities. And here's the thing you couldn't imagine today. The Daily Telegraph published it - sheet music and all - on Christmas Eve 1927.

In the Night Lab

It's that time again when it becomes respectable to dig out your Christmas CDs as tomorrow the great chocolate countdown begins. (Hands up who can remember advent calendars without chocolate? Boring, weren't they?) Yes, despite my repeated cries of 'Bah, Humbug', I have to give and get a quick coating of tinsel.

A number of years ago, on my old blog on Nature Network, a miniature masterpiece evolved. It was an 'anyone can contribute a line' poem, based on 'Twas the Night Before Christmas' but set in a lab. Yes, folks, this is both lab lit and evolutionary poetry. I feel it deserves to be preserved (indeed pickled), so I like to dig it out on a regular basis.

For those who like their pomes read out (here with sound effects by the excellent Graham Steel), here it is:


And for those who are members of the campaign for real written words, here it is in all its glory:

Twas the night before Christmas and all through the lab
Not a Gilson was stirring, not even one jab.

On the bench, ’twixt a novel by Jennifer Rohn
And the paper rejected by Henry’s iPhone
Lay a leg, still trembling and covered in gore
And Frankenstein sighed ‘I can’t take this no more’.

He exclaimed panic struck, as he took in the scene,
of horrendous results from NN’s latest meme.
‘having one extra leg wasn’t part of the plan
to create a new species, anatomized man’.

And then out of the blue, ‘twas a bump in the night
A girrafe ’pon a unicycle, starting a fight
Held back by a keeper all smiling with glee,
It was then that I knew that it was Santa Gee.

His iphone, it jingled, his crocs were so pink,
It was all I could do to stammer and blink.
‘There you are’ cursed old Frank’stein, approaching the Gee,
‘Call off the girrafe, and hand over the fee.’

“The Beast” then leaped up, from O’Hara’s new leg
Attacked Santa Gee and his elf, Brian Clegg.
One sweep of the sack and the beast was laid out
When hoof of girrafe gave a terminal clout.

Then its leg fell off quaintly, with a sad little ‘plonk’,
Santa Gee, from his sled, gave a loud, angry honk
And the mask on his face slipped – sadly ’twas loose -
To reveal not a man but a fat Christmas Goose.

To Frankenstein’s horror, the bird reared up high
He realized then that this goose could not fly.
So he grabbed the elf Clegg, who stood by buggy-eyed
and hoisting him up with great gusto he cried:

“O’Hara and Beast, I have them at last.
Sprinkle on Ritalin, for a tasty repast.”
But five minutes had lapsed, so the beast was asleep
Having dreams that were complex, clever and deep:

Half warthog, half carrot? What would look nice?
Half girrafe, half O’Hara? Yes! Made in a trice.
He dreamed a solution, to this horrid scene:
Unite the spare legs! To waste them is mean!

Much later that evening, the creature awoke!
One Bob-leg, one g’raffe leg! He rose up and spoke:
“Beloved creator, I wish you’d not meddle,
My unicycle now needs a quite different pedal."


Like all truly great works of art, it helps to have some background knowledge. The named persons were all contributors to Nature Network. 'The Beast' is Bob O'Hara's cat. And for obscure reasons 'a unicycling girrafe [sic]' was an in-joke.

Beware the average

Which one's the average house?I was struck by an item on the local news this morning saying that the average house price in the UK was £163,910 according to the Nationwide Building Society. This seemed a dubious statistic. Why? Because the average (or mean) is not a good measure of a distribution that isn't symmetrical. It's highly misleading. That's because the vast majority of houses in the UK are worth less than the average house price - and that is downright confusing.

Let's look at a simpler example to see what's going on. Imagine we have a room full of people and take their average earnings. Then we throw Bill Gates into the room. Bill's vast income would really bump up the average - so probably everyone else in the room would earn less than the average. The new average would not be representative of the room as a whole.

The reason a relatively small number of cases (in our room, Bill) can have a big impact is because the distribution - the spread of the incomes - is not symmetrical. Let's say the average income before Bill entered the room was £26,000 a year. Then the absolute maximum anyone can fall below that average is by £26,000. But there is no limit to how far above the average you can be. In Bill's case, he will be millions higher. So he has a much bigger impact on the average than a poor person does.

In such cases, the median is a very valuable number to know. This is just the middle value. We put all the people in a row in order of earnings and pick the middle number. With a distribution like our room - or house prices - the median gives us a much better feel for what a typical value is like than the average.

Which takes us back to the Nationwide. I took the liberty of dropping their Chief Economist, Robert Gardner an email and he was kind enough to call me back within 10 minutes (and to email through some bumf). You really wouldn't expect a financial institution to make such a basic statistical mistake... and they haven't. What the Nationwide repeatedly calls an average in their press releases isn't a simple average at all. Instead they stratify the data according to region, type of house and so forth and produce a rather messy weighted figure that could arguably be said to be the typical value - but it certainly isn't an average.

You can argue whether they should be rather clearer about just what the figure they are producing is, rather than calling it the average house price as they do, but at least it is a meaningful figure.

In other statistics, I'm afraid the press simply gets the words wrong. Quite often a government bureau will publish a median value and an average - they do so on earnings, for instance. What the media often does is to take the median value, because it's more meaningful, but calls it the average (presumably because they think the poor public can't cope with a hard word like 'median'). That's just bad journalism.

This distortion of the average is something that politicians wishing to attack another party and not being too scrupulous about their statistics can use to their advantage. If we want to tax those on high earnings and find the tax hits someone on the average wage, then there is an outcry, because that seems to imply that it hits the majority of ordinary people – but the majority actually earn less than the average wage. The naughty politician can play the numbers even more effectively by putting two people on an average wage into a household. Now we are not only using individuals that earn more than most, but a household where both partners do so. This pushes their collective income up so high that it puts the household in the top 25 per cent of all households, even though we are talking about two people who are on an average wage.

There's a simple message. Whenever you hear 'average' in statistics on the news or see them presented, it's worth taking the numbers with a pinch of salt unless you can verify just what lies behind that value.

Turing's statue

There is a Turing statue in Manchester, but frankly
it's unrecognisable. You can do better, guys.There is nothing editors like more than anniversaries. Recently I suggested a feature to a magazine. 'It could work,' they said, 'as long as you can find an anniversary to tie it to. We need a hook.' Frankly, this is a load of rubbish. The reading public really doesn't care why a magazine or newspaper is coming up with a particular story as long as it's interesting. But editors feel they have to devise a justification. They need a reason that a particular story should be used, so they arbitrarily use the factor of a significant date. It keeps them happy, bless them.

This being the case, we can expect a flood of books on Alan Turing as it was the 100th anniversary (wey-hey!) of his birth in June. Leaving aside the fact Turing would certainly have preferred a binary anniversary (2018 will be the 1000000th anniversary of his death), I'm currently reading the first of these books for review. I don't want to talk about that book itself here (it's Turing: Pioneer of the Information Age by Jack Copeland ) as it will be reviewed on popularscience.co.uk very soon - suffice it to say it's shaping up well - but I would like to shamelessly steal what appears to be Jack Copeland's thesis.

This is that the remarkable things we remember Turing for are probably his lesser contributions to the world. Many know that Turing was one of the leading codebreakers dealing with the Enigma and Tunny machines at Bletchley Park during the Second World War. And we may well remember Turing's contributions to the idea of artificial intelligence, with the 'Turing test' that is supposed to show whether or not a computer can pass itself off as a human being. And the tragic end to his life, committing suicide after being handled terribly by the ungrateful authorities (who should have been treating him like a national hero) because he was a homosexual. But there is even more to this remarkable man who, in his biography, sometimes comes across a little like Sheldon in The Big Bang Theory.

Arguably the reason we should really remember Turing is that at the most fundamental level he invented the modern computer. Forget Babbage - well, no don't forget him, but cast him, as Copeland does as grandfather of the computer. It was Turing that dreamed up the real thing. In a sense it was just a throwaway initially. His theoretical universal computing machine was devised as a way of exploring an abstruse (though important) aspect of mathematics. But as Turing himself came to realise, this was much more. In effect, what Turing did was invent computer science. Pretty well everything else everyone else has done that is labelled 'computer science' is the engineering to put Turing's vision into practice. Turing's work was the 'theory of everything' of computing.

Companies like IBM, Apple, Microsoft and Google should be putting up statues in his honour all around the world faster than you can say 'serious profits.'

Look first, then tell the world

With some regularity I get sent emails about scams, viruses and strange things that Facebook is going to do. Almost always these are accompanied by a request to pass them on the world and its aunty. And there's the thing. Because almost always these dire warnings (some of them very dire) are themselves a form of virus. What they describe is totally fictional, a hoax that by panicking people into spreading the word, reproduces and travels the world. It is this 'chain letter' effect that is, in fact, the awful payload.

Whenever I get these warning emails and Facebook messages my first step is to pop over to Snopes (thanks to Andy Grüneberg for introducing this to me many years ago). Snopes is primarily a way of checking out urban myths, but most of the time these spoof warnings also get a write-up.

So, for instance, I recently got an email from someone, asking me to pass on to everyone I know a warning about cards being left by Parcel Delivery Service. Anyone who rang up to have their parcel redirected got landed with a bill of £315 for making a phone call to a premium rate number. There was, of course, no parcel. This warning is vastly out of date. The scam did exist - but the bill was £9 not £315. More to the point, the number being warned about was deactivated in 2005. It was a real problem (and may well still be with a different name and number) - but the specific warning doing the rounds in 2012 was 7 years out of date. It was a ghost warning, a Flying Dutchman of a warning.

I was also warned about a virus that showed a happy smiling Gordon Brown (okay, that's weird, I admit). PLEASE INFORM EVERYONE said the much copied message. Open the attachment with Gordon's pic and your PC will be trashed by an 'Olympic Torch' that burns your whole hard disc. Don't get me wrong. Viruses exist and can do damage. But whenever you get an email or Facebook message it's worth checking, because chances are that these 'Pass it on to everyone' messages are fakes.

When I've established it's a fake there's the difficult decision. It's not to bad if the warning was simply a Facebook post. You can just add a comment. But it's harder when someone has just sent the warning to everyone in their address book. Do you point out it's a spoof? Probably you should, as really they should be warning all their friends not to pass on this message. But it always seems a bit mean.

So here's the thing. Next time you hear about a terrible email that will make your computer explode if you open it, or the latest phone scam, or Facebook's latest outrageous terms and conditions, pop over to Snopes first (another good source is Hoax Slayer) pop in a few keywords and check it out. You could save yourself time and embarrassment.