What do you get when you take a Mac and add the Nintendo Wiimote? Why, DarwiinRemote, of course. This little app, which is still rough around the corners, lets you use your Wiimote (that being the new controller that comes with Nintendo's next gen console, the Wii) and use it as if it were an Apple Remote (only on Macs that have an IR sensor of course).
Useful? Not really. Cool? You bet.
Update: It would seem the Wiimote uses Bluetooth, so most Macs can join in on the fun. Thanks to everyone in the comments for correcting me.