My new obsession: Geocaching

[image error]Seriously, how have I never heard of this before? And now that I have heard of it, does that mean it's jumped the shark? (See: Birkenstocks, which I finally decided I liked a good 10 years after college.) What it is: a massive, world-wide treasure hunt. You download an app on your iPhone, and are able to look for more than 900,000 "caches" that are hidden, well, everywhere. They come in all shapes and sizes: They can be as small as a thimble or as big as a suitcase (this is my friend Geoff, with