Download Youtube Videos Directly W/o Using any software

Download youtube videos directly..
Just download this javascript

http://www.ziddu.com/download/1957722/hack_youtube_videos_javascript.zip.html

Steps for using this script:
1.Go to Youtube.com
2.Click on the required video.
3.Address will be like this

http://www.youtube.com/watch?v=3twb7PY0vbM&feature=related

4.Now copy the javascript which you had downloaded.
5.Remove the address in ADDRESS BAR and paste javascript & hit enter.You'd done.
NJOY..;)