Just throwing this out there...
The iRing. I gotta admit, I laughed it off at first, but seeing these recent articles about Apple's patents for a Wii-like controller, maybe it
is in the shape of a ring. Something that can be worn and not held. It'd have mouse like capablities and with accelerometer, giving it a "depth". Multi-touch-less and 3-D. Could even come with a button which you could depress with your thumb. Total speculation, but it got me thinking...