Wedding registry, schmedding registry! In lieu of a boring blender or cutlery set, Mikai Hart built his friend what has to be regarded as one of the coolest wedding gifts ever: a working, GPS-equipped global treasure hunt puzzle. Or, as he calls it, a "Reverse Geocaching Puzzle."

Built for a friend who was getting married and moving to France, the case will only give up its contents and open up when the GPS sensor registers the correct coordinates in France.