Geocaching is awesome. You get to see new things in your own city that you may not have known existed and go on mini adventures. After geocaching for a few years, I've moved on to terracaching which is the same thing, only caches must first be approved by your sponsors before they're listed. It also incorporates a point system.
"Maybe more clever (not necessarly more expensive) items could make finding the box even more fun."
It's really not about trading things, or even finding the box. It's looking for the box, the journey so to speak that counts, kind of like touring. Although, first to find (FTF) prizes can be pretty cool.