Check out Flickr user Rumtopf’s fancy take on the reverse geocache box. For those who don’t know, a reverse geocache is a box that unlocks itself when the GPS sensor inside senses that it’s in a specific spot on the globe. Rumtopf used a snazzy doorbell button to wake an Arduino, which checks the GPS and displays the distance from that spot on an LCD. He also used a magnetic child safety lock as a backdoor to access the inside of the briefcase in case of malfunction. And if you’re ever in a position which requires you to solve a reverse geocache, he also created a web-based utility to help narrow down the location and unlock your prize, whatever it may be. [via the MAKE Flickr pool]

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