Geocaching

TREND A globe-trotting treasure hunt in which players search for hidden prizes using handheld navigation gadgets

HOW IT STARTED The military opened up its global positioning system to civilians, and Christmas came early for nerds everywhere

JUDGMENT CALL Anything that exposes geeks to sunlight can't be bad

Right now, in the middle of a Joshua-tree forest in southwestern Utah, there's a Folgers coffee can containing a pen, a notebook and a large rubber snake. It's just one of hundreds of prizes in the global scavenger hunt known as geocaching. All you have to do to win it is to make your way to 37.0939[degrees] N by 113.9429[degrees] W and pick it up.

Geocaching is a new sport made possible by a satellite-based technology called GPS (global positioning system), which enables users to pinpoint their exact latitude and longitude on the earth's surface to an absurd number of decimal places. Last year early adopters in the Portland, Ore., area began hiding little stashes of CDs, action figures, Band Aids and other goodies in exotic locations--on a mountaintop, underwater, hanging off a cliff face--and posting the coordinates on the Internet as a challenge to their fellow nerds. The idea is that once you find a cache, you take the prize but leave something else for the next person and sign the log book on your way out. According to geocaching.com there are now caches in all 50 states and in 46 countries. Later this summer 20th Century Fox will stash props from the movie Planet of the Apes in geocaches around the country as part of a stunt-marketing campaign. Now that Hollywood has discovered it, look for more than a rubber snake in a coffee can.

--By Lev Grossman