Geocaches in Libraries and creating a Letterbox Maker Space program

I was doing some reading about geocaching, and found that there are some libraries that have allowed cachers to place a cache within the stacks (best place is probably the reference stacks). Laura Goodwin describes her experience (in the comments section of the post) of finding a cache at a library, where the coordinates for the cache took her to the front door of her library and then she figured out the name of the cache, given in Dewey decimal "code," would reveal the actual location of the cached item.

Geocachers searching for the cache hunt through the stacks then sign the log once they find the book, which could be hollowed out to contain additional items. I see a letterbox hybrid (scroll down on the linked page for the description) as being especially cool and could even be part of a maker space (individual) program where participants make a stamp to add to the letterbox log. (Letterboxing is itself an activity that is similar to geocaching, but rather than use GPS technology to mark the location of the letterbox, orienteering skills as well as problem solving of hints and clues are required.) The book wouldn't even have to be cataloged! 

A Maker Space Letterbox Activity could be:

• find the letterbox cache, 
• "check out" the book which would really involve getting the maker space tools
•  carve the stamp, then ink and add your personalized stamp to the letterbox's logbook
• return the tools and letterbox cache/book to the library
• go home with your new stamp and perhaps take up letterboxing

Issues with this activity

• carving tools are sharp and could cut the person if they don't use them correctly
• ongoing cost of the stamp material for carving
• messiness of the inks (which is why it would all be contained in the makerspace!)

Here's an awesome letterbox found in a pill bottle. A healthcare blog posted it as a thematically related activity they suggest for nurses!

FreeSpirited1 has created a list of geocaches located in libraries on geocaching.com. (You don't have to be a member of the site to see the list, but in order to see the full descriptions of each cache, you'll need a free membership.)