Trying to install a Logitech Quickcam for notebooks webcam on my wife’s Mac and it doesn’t detect it. After a little searching, I found macam. It supports hundreds of webcams previously unsupported with OS X. Installed it, camera works! However, the camera was underpowered for use with Photo Booth and iChat. I resorted to purchasing the $39 XBOX 360 Webcam. It’s not quite as nice as the iSight, but works in OS X natively, and works with both Photo Booth, and iChat.