I read this book on Kindle. I'd suggest reading it in paper instead, as some of the lists he makes are unintelligible regardless of the font size chosen on the Kindle.

While Allen does mention many of the methods and support materials with which anyone who's obsessed with organization is familiar, he does take the whole concept of organizing to a new level. While it still seems a bit counter-intuitive to me (probably because of the amount of effort you need to make to set the system up), I think that his system, if properly used even partially, will help you get things done.

Two of the most valuable concepts are: having your email in box actually be an inbox and splitting any multi-step process/project down into smaller, more manageable chunks. The most important question to ask is: What next action can I take (on a particular project)? The next action (which reminds me of SARK's micromovements, but actually isn't the same re: its linear approach to time) lets you concentrate on something that's do-able instead of panicing.