There are tons of websites, book-marklets and Firefox extensions that let you download youtube video onto your hard drive, YouRipper takes a different route.
YouRipper is a desktop based utility that takes the URL of the Youtube video and saves it to any folder on your hard disk in the popular FLV format.You may think of YouRipper as just another video download manager, the interesting part is that it accepts the cryptic Youtube video URL and decodes it to find the actual location of the flv video bypassing the need to use services like Keepvid or Greasemonkey scripts.
YouRipper should definitely appeal to users who look to downloading youtube videos outside the web browser or find Firefox extensions too geeky to use. Wish it could save in the AVI format and supported pause-resume like other download clients... Enjoy!