We've seen some great hacks with the Wii controllers since the console first arrived, and things could get even easier if Todbot has his way. He's launched the WiiChuck, a tiny plug-in board that slots into the plug of the Wii Nunchuck, and allows you to access all of the controller's connections - its 2-axis joystick, two buttons and 3-axis ±2g accelerometer - without needing to cut any of the cables.
A little soldering to the four connectors on the other end of the PCB and you've got a way to hook up to the nunchuck for your own projects but a controller you can then plug back into your Wiimote for some standard gaming. Various open-source libraries are available, so if you've wondered about hooking the nunchuck up to an Arduino controller then here's the most non-destructive way of doing it.
The WiiChuck adapter retails for a frankly miniscule $2.95 - less if you're ordering more than a handful of them - and is available now. More details on the hardware specifications here.