Guessed by theoblue

It cannot be an agility game because it has no integral power source. It must be tethered to a power source. I guess that it draws power from a PC through the USB socket on the Duemilanove. The suction cup will only adhere to a smooth surface so it must need to be fixed to something smooth. Assuming that the headphones have their own jack plug, the additional plug must deliver an audio signal into the device. Does it somehow 'enhance' an iPod or mobile phone by modulating the music according to movement? But then what does the LED display add? And how persistent is the push button?