From M5 Technology:
Fast Youtube Downloader is an extremely fast and comprehensive Youtube downloader and converter. The program allows you to download videos, including HD and HQ videos from Youtube and convert them to different video format.
Fast Youtube Downloader - Free Edition enables you to watch your favorite videos from YouTube wherever and whenever you want.
All you have to do is insert the Youtube URL and click Download. It will convert your videos for iPad, iPod, iPhone, PSP, Cell Phone, Windows Media, and XVid formats.
Fast Youtube Downloader also supports high quality and Full High Definition video.