Tilt based mouse replacement

Over a recent online discussion with Wade - we formulated a brilliant plan for combating RSI (something we coders can suffer from at times). Basically the plan is to use a 2-axis accelerometer as a tilt meter (which works well if you are fairly stationary as it responds primarily to gravity). This would be connected through some wireless interface (possibly BlueTooth) back to the computer (although the initial prototype will probably be wired). As you tilt your head forward and back, the mouse cursor would move forward and back - likewise with side to side. I'm very pleased with this idea and hope to show it off at work soon (along with my other half-dozen projects that haven’t quite gotten off the ground yet).
Besides normal day to day use, I think this would work particularly well for first-person games.