This is in the running for coolest gift ever: The Reverse Geocache Puzzle Box (“”You are — how you say in English? — a BASTARD!“). Here’s a nice”video overview“:http://www.youtube.com/watch?v=Lu7IysgaZf8. See also”this variation“:http://electricgeocaching.blogspot.com/2010/08/gps-puzzle-box.html, the”Woodpecker Puzzle Cache“:http://electricgeocaching.blogspot.com/2010/08/woodpecker-puzzle-cache.html and these”wind-up birds":http://hcgilje.wordpress.com/2008/09/04/wind-up-birds/.