Although it has been in existence for around 15 years or so, you may not have ever heard about geocaching. There are roughly ten million ‘geocachers’ around the world, adventurers who use their GPS devices to go on treasure hunts in the real world. The treasure they are hunting for? Geocaches. For the most part geocaches are containers (of any size) that have been hidden with a logbook (and sometimes knickknacks) inside. The goal is for other geocachers to find the cache, sign the logbook, and maybe trade some collectables.