Staging a Treasure Hunt
Since the early 2000s, GPS enthusiasts have used the devices to set up high-tech treasure hunts. Geocaching hobbyists hide caches of trinkets such as souvenir coins or toy plastic animals in various locations that they've plotted on treasure maps, and then post the maps online on sites such as Geocaching.com, so that others can search for the prizes.
Some Geocaching events are staged in parks, but there also are treasures secreted in urban neighborhoods as well. Geocaching participants can use mobile phones or iPads in their search, but the truly serious invest several hundred dollars in hand-held GPS units that have greater accuracy [source: Caldwell].