Using the camera sounds cool, but I don't know that I would want to be sliding the back of my phone around on my desk. Even with Invisishield on it.
Here's a link to the GRemote post over at XDA. There are a couple of different functions that are included. The "air mouse" is one as well as a touch pad setup.
http://forum.xda-developers.com/showthread.php?t=427097