The Hamster Synth Ball is a musical instrument comprised of two main parts:

The Hamster Synth Controller
The Magic Bean Tin Receiver Synth

The Controller is essentially an Accelorometer, an Atmel168 Chip, and an XBee Radio Transmitter in a hamster ball. The accelorometer information is scaled by the atmel chip and the data is sent wirelessly by the xbee to the receiver.

The receiver then takes this control data and uses it as PWM info to fade two LEDs on the receiver synth. These LEDs are then used to drive photocells connected to an oscillator to control its tone and pitch.

A video would really explain everything much better. Sadly, no video was ever shot.