UPDATE – I am now selling the wireless controller on eBay.
I recently finished the Xbox 360 wireless tilt controller mod. This is the same as my Xbox 360 tilt controller, only it is done to the wireless version of the controller as opposed to the wired. I did the mod using a 3V tiltBoard (now available for pre-order). With this controller I added a switch that allows you to switch between using the tilt of the controller and the left analog stick for input. I demonstrate using the switch in the video when playing Full Auto (car racing game). I am using the analog stick at the beginning until I switch to the tiltBoard slightly into the race.
For those interested in getting a tiltBoard and doing this themselves, I will be making a video how-to of the entire process. Look for that in the near future.
For those worried about lag, this is the same code and processor as used in the wired one. It should have the exact same response it does. Check out its lag here.