Outdoor activity for geeks

Have recently got GPS receiver to use in a car, so we tried new outdoors activity today - Geocaching.

It's basically "find a treasure" kind of game, played globaly by thousands of players. Geeky part is that you need GPS of some kind to be able to locate the cache.
Fun part is that even with GPS you need to look very carefuly for possible hiding place. And caches are usually near some interesting point like great view or various landmarks.

We also tested if dog can help with finding the cache, but so far no significant contribution to the process from koudy ;) If you're geek, into hiking and generally like challenges, it's really worth considering.