1-Click YouTube Download is a lite, easy to use, open source Firefox add-on that allows you to download videos from YouTube with a single click and save it to your local computer.
The add-on adds small links in YouTube to download videos and music in 3GP, MP4 HD (High Definition), MP4 High-Quality and FLV.
This is one of the lightest and simple tools to download videos from YouTube. 1 Click - and the videos is already on your computer!
Link to Free Download (http://www.theinfostride.com/forum/index.php?action=downloads;sa=view;down=55)