The Korg WaveDrum Mini is a drum machine that allows you to use any surface that will transmit a vibration to the little clip. That means you could clip it to a wheelchair tray, a door, a plastic bottle of drink and many other things.
Reminds me a bit of Let's Tap on the Wii. Actually having those two hooked up together might be hugely entertaining cause and effect (splatter ink paint on screen, and sounds from the Korg).
Found via: Applaud Interactive.