This reverse geocache box reminds us of something out of Mission: Impossible -- the second-run of the TV series, not that dreadful Tom Cruise franchise -- only it won't self-destruct in five minutes. It will, however, unlock when it reaches a pre-programmed location. Like the Deluxe Reverse Geocache, this box gives its holder a mission should they choose to accept: use the display to find the box's final resting spot. Unlike its predecessor, this one uses three nixie tubes, not an LCD screen, to track the box's distance from its destination. A built-in Arduino GPS
