ClipNabber é uma ferramenta que facilita a forma de baixar vídeos online de websites como YouTube, Google Video, MetaCafe, DailyMotion, MySpace, Break, iFilm, Veoh, entre outros. Basta colocar a URL do vídeo online e voilá em instantes você terá a opção para dar o download do vídeo.
fonte: Xyberneticos
Another site that is good for this is the one I just made 😛
http://clipkeeper.co.cc it has support for about 30 different video sites.
It also has video downloader search bars that integrate with both FireFox 2.x and Internet Explorer 7.x-11.x Search Bar feature.
In addition it allows you to add Download links with videos you embed online with a single line of code and no javascript which allows use of the links on MySpace and other sites that do not allow javascript.