I am in the market for an accelerometer and figured I'd ask the LMR forum before I ran out an bought one. I have tons of goodies to swap; iDuino, Vex pneumatics, omni wheels, etc.
Fun Gizmos has a wiichuck adapter, too. I like using the nunchuck because you get a three axis accelerometer, an analog joystick and 2 buttons and it's all i2c. Even if you don't need the buttons, it's still a pretty good deal.
Note - you don't need the remote, just the nunchuck.
please note that buying a controller for the Nintendo Wii game console will get you an accelerometer cheaper than buying just the accelerometer from an electronics outlet.
Here's a set on ebay for only 9.00 USD. included in that price you get som other electronic components for salvaging as well.
If you buy one of the Wii controllers/nunchucks that not made by Nintendo you'll get it even cheaper.