The operation is quite simple, the USB cable connects to a thumb drive inside the device. The thumb drive has been cracked open to expose the circuit board, USB power and the drive LED output has been tapped into. These 3 points are wired to a small circuit board, there is a circuit that stretches the drive pulses into an on or off signal that is buffered by a transistor to power the internal motor and LED lights. The pulse stretcher was needed since the USB drive would flash when it was being accessed. This would have caused the motor action to be very jerky and the internal lights would also have flashed.
The cost to purchase all the parts for this project should be between $10 and $15 depending on the deal you can get for the USB thumb drive and assuming that you have a few items in your parts junk box. Construction time should be 3 to 4 hours but it took me longer since I took a ton of pictures along the way and has some belt drive (or should I say rubber band drive) issues.
I am posting this project here since many of you may not have seen it on Hacked Gadgets.