Fun
Saladin's Puzzle.
12 coins, one is of different weight. Measure on a balance which one is false and if it is heavier or lighter. Solved with information theory.
Rubik's Cube solution (oplossing. Dutch):
rubik.pdf
Printer Music (Arduino)
video:
schematics:
Arduino program
Photos of Stallinga @ Flicker
Prof. Peter Stallinga