Geocaching is a high-tech treasure hunt in which participants use GPS receivers to find caches which have been hidden by other geocachers. The caches are of different sizes, from 35mm film cannisters to plastic lunch boxes to large metal ammo cases and contain a variety of items which can be swapped out (though it is not necessary to do so, and often the search is the fun part anyway). There are thousands of caches hidden all around the globe and I find it a good way to plan a walk or bike ride and discover new places.

(PedroTheLion is my account name on www.geocaching.com - named after the band.)