World's 2nd smallest working train set

This is my Train Set in a Cheese box. They are 1/2 inch pieces cut out of wine cork, painted and embedded with magnets. Servo motor with a cardboard disc guides the train across the the tracks. It's a PWM circuit powered by a 555 timer. The sound comes from a Radio Shack recorder Module.


                                     
                                                                    http://www.youtube.com/watch?v=1b90SFUmIv4