From the Detect And Zero Rightmost One blog:

Electronic Geocoin

I used pcb-rnd to create a Printed Circuit Board (PCB) with a “geographical” shape, the shape of the state of Florida, for a Christmas present of six assembled devices for my brother who lives in Ocala Florida and is an avid geocacher. His geocache handle is marked on the board (obscured in video for his privacy) as is a space to write a tracking number. The LED at the “OCALA” logo will flash every 30 seconds. These electronic circuits are “trackables” that he will deposit in a geocache with the idea that it will be moved along. However, trackables are often kept by the finder as a souvenir.

The boards were made for me by OSHPark and hand assembled.