Script Summary: Creates a download link, link is added to the description box of the video. NOTE: You need to open the link in a new tab as it does not support theater mode.
Works on Google chrome also, tested using version 18 on Windows 7
Update: 31st March 2012, fix for facebook source change
Update: Changed for new facebook layout converging videos to photo.php
Open the video link in a new tab(Ctrl+Click), the link is added after the description of the video on the right side below the video.
Author: Karthic Kumaran