I've never been a fan of Web Cams, but my Mac Book Pro did not come with the option of not having one. Since I'm a bit on the paranoid I want a way to disable the camera.
The easist way, but not the best way is to move or rename a file. The file that we're looking for is the QuickTimeUSBVDCDIgitizer.component file. This file is located in the /System/Library/QuickTime folder.
What I did to disable my iSight was move the file up a directory. When any application tries to access the camera, it will say it's in use.
Right now I'm not aware of any other way to disable the camera, but I will continue to look into it. I'm also looking into disabling the internal microphone.