Think a 2 digit number (from 10 to 99), subtract from it the two digits and keep the result in mind. (Example: 18, 18-1-8 = 9) Click the wooden door and search your number (using the brown arrows or the arrow keys). Keep in your mind the thing which is above your number. Click the door again and stare into the crystal ball. Concentrate on the thing, the more you concentrate, the better I can read your mind.
Mind Reader! I was inspired by frank1281 (Mind Reader-1) gamegeek118 (Mind Reader) and scmb1 (Magic Mind Reader). I used Gimp for the wooden surface. Here is a video in German: http://www.gimpforum.de/showthread.php?t=13763 The other things I've drawn using Inkscape and Scratch.