iSight
http://www.intergalactic.de/pages/iSight.html
"Here’s a little utility which captures a frame from an iSight camera and writes it to a file."
Use your MacBook camera to see who's using your laptop | FlatulentFish
http://www.flatulentfish.com/drupal/node/24
"Dylan O'Donnel published a simple method to capture a user's picture using the MacBook's built-in camera when a user logs in."
Evil Mad Scientist Laboratories - Make a Video Feedback Screen Saver in Quartz Composer
http://www.evilmadscientist.com/article.php/VideoFeedback
"we'll build a video feedback screen saver that can take input from an iSight camera."
