We'll readily admit that most Arduino mods tend to be exercises in creativity (and eccentricity) with little real world utility, which is why this one piqued our interest. A wedding present conceived of and built by Mikal Hart, the box you see above is set to only open in one particular geographic location, and the puzzle of it is to find out where that might be. You're allowed 50 attempts at opening the box by hitting the button next to the LCD screen, which in turn gives you a distance from, but not direction to, your destination. What tickles us about this idea,