Take a picture with the iSight camera when a folder is opened

This script describes an AppleScript that uses Imagesnap, a public-domain command line tool, to take a photo with the built-in iSight camera when a specified file is opened. It saves the photo as a JPEG with a filename based on the time/date, and then hides the JPEG. The light by the side of the camera will flash briefly when the snap is taken.