Remember treasure maps? Those enchanting childhood props with their promise of buried loot? Now there's a digital equivalent. Equipped with a handheld Global Positioning System (GPS) unit like Garmin's Geko 201 (about €200) an electronic device the size of a mobile phone that determines the precise latitude and longitude of the holder's position by picking up a radio signal from several satellites you can take part in "geocaching," a techno-treasure hunt.
Here's how it works. Select the coordinates for a cache usually a weatherproof container filled with some cheap trinkets posted on one...
