Geocaching is a treasure hunting game where you use a GPS to hide and seek containers with other participants in the activity. Geocaching.com is the listing service for geocaches around the world.
Over my Spring break I got to do some caching and it revitalized my interest in geocaching. It is quite fun and healthy activity and it's fun for the kids too. I'm also Rantar on that site if you'd like to friend me or look for me in a log near you. I'm closing on 1000 finds now!