One of the features of the iPhone is that it acts as a GPS receiver. I've been using this feature since I got mine to geotag photos, search for nearby restaurants or stores, and get driving directions. But when I got some extra time with my daughter this past weekend, I realized there was another use I could put it to: geocaching.
Geocaching is a modern version of the good, old-fashioned treasure hunt. You get the coordinates and description of a cache from the website, then set off with a GPS unit to go locate it. Some caches containe just a log book to sign, others have small treasures to trade. All of them are well hidden, and a great deal of fun to seek.
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