As soon as a discovered what geocaching was, I signed up and went on my first exploration. If you've not heard of it before, Geocaching is a sport/hobby that involves using geographical coordinates and a GPS to look for containers hidden in the woods, in cities, on top of mountains, underwater, in lamp posts, inside of logs, etc. When you find one, you sign a log to prove you were there, and optionally take a prize from the cache, replacing it with a new one of equal or greater value. It's not about the prizes though - they tend to be pretty lame. The fun is in exploring trails and areas you might never have visited otherwise - it's a great way to discover new terrain. It can also become a semi-competitive sport, once you get into it. Geocachers compete to find the most caches in an area, to find caches in every county or state, etc.