Demon Monkey shooter is an FPS that uses a squash racket as its main input device, no strings attached (pun intended). The racket's movements are tracked using a Vicon motion capture system. This is quite a step up from the Wiimote. And yes, we can probably do tennis too.

Demon Monkey Shooter from Zi Ye on Vimeo.

Toshiba's flexible LCD panel can be grabbed and physically bent to zoom in or out using Google Earth.