This wasn't what I was thinking about, but that's another idea. But, what I was actually trying to achieve here was: with a properly aimed iSight it could follow finger movements so you could point and drag your finger in the air, and it would move the mouse. Only then when you moved your hand out of the way to flick it or some motion to click, it would follow that movement? or be smart enough to stop tracking? Also if the tracker can't be made you could program gestures to do very common things. For example, you could wave your hand in front of iSight, and boom, Expose. You could wave your hand down very quickly and boom, the IM you were looking at would close. This actually could go somewhere. Just think, before the PowerPC, nobody dreamed of speech recognition. I don't even have broadband but when that wonderful day comes when I buy my Mac I'm going to get an iSight for this among other things, like a photoblog. Anyway. I just wonder if this is possibile.