I think we've told a lot of people about geocaching, but if you haven't heard you should check out this website: www.geocaching.com Become a member for free!
From here you can find coordinates for caches that people have hidden all over the world; but also in your neck of the woods. You don't have to have a GPS, thanks to google you can can map anything pretty accurately... but having a GPS is really the main part of the game.
So you pick a treasure that you want to find, download it to your GPS and go look for it. They are hidden in trees and buildings and underwater. A lot of them out here seem to be ammo cans and film canisters. As I understand it, sometimes people put money in them so it's a real prize to be the FTF [first to find]. We are having lots of fun trekking through woodsy areas of our surrounding neighborhoods. It's usually somewhere that we otherwise wouldn't go. You have to be stealthy - part of the idea is to keep the cache a secret and not draw attention to the fact that there is something hidden in the big tree stump. We are devising where to hide our own caches. We are keeping a journal and take lots of pictures of our adventures. I also log back onto the website and report when we find a cache & any pertinent details. Some people have found thousands. We're up to 5, I think. Our "team" is named SPAZ-ZAH! [Sare Pete And Zoe-Zah]
The song in the video is "Sleepy Tigers" by Her Space Holiday.