There are a few breakout boards available, like the Wii Chuck and the Nunchucky, that will let you connect a Wii Nunchuck to whatever electronics project you like. They’re designed for Arduino, of course. I picked one up to play with it. It’s quite simple to put together and it’ll read out its accelerometer data to the PC, or into a variable. It took about five minutes to decide to turn it into a musical instrument.
The Arduino reads the X and Y data off of the nunchuck and turns them into PWM tones to play. As you twist and turn the thing, it changes the frequency coming out of the speaker. Meanwhile it can also read in the button presses and the thumb stick data… I haven’t utilized them for anything yet, but they could be used to shift registers or something, I dunno.
It’s all in an extremely rough state, not much more than a proof of concept. And it doesn’t exactly make music, just noise. There’s a whole hell of a lot of polish that would need to happen to properly call it useful. But more than anything it’s a good way to play with what an accelerometer can do.