I took up another new hobby, just today really. Geocaching is a sort of sport where someone will hide a 'cache', usually a small box of some sort, in an interesting location. They then post the GPS coordinates of that location plus whatever amount of hint information they care to provide. Then, others use their GPS devices to track down these caches. The caches almost always contain a logbook of some sort, maybe as simple as a piece of people, so that people who find the cache can leave their signature. They may also include presents; these can be taken or left behind as the finder desires, and it's encouraged to bring new presents as well.
After spending some time at the Power to the Peaceful festival, I wandered off in search of some of the caches whose coordinates I had written down. The trek took me through some corners of Golden Gate Park that I never would have found on my own. It's a good excuse to go on a hike. I suspect some people drive to near the location of the caches, but for me most of the fun lies in walking there.
I attempted to find 3 caches today, but I was only successful on my last one. GPS coordinates will get you most of the way there, but they don't tell you elevation; the search for this last cache took me up and down stairways in a parking garage, trying to find my way ever higher to get at the exact point that was being pointed towards. Eventually I found it, and left my name.
Caches apparently exist in the 'wild' as well as in cities; some may exist on cliff-sides and require climbing to, or be under water and require scuba gear to access. That's extreme, though. Mostly they're just hidden in good locations.
My first cache was found somewhere in this picture. It was reasonably well-hidden; no one is going to run across it accidentally.
