Here's a little device I made recently as a present. It's a box that won't open until the recipient discovers the secret of where on the planet to move it. :slight_smile: http://arduiniana.org/2009/10/the-reverse-geocache-puzzle/ Mikal

The Reverse Geocache Puzzle

system October 16, 2009, 5:25pm 6

This was inspiring!

Insanely cool