How to install U-Tube Downloaded on Ubuntu 

ClipGrab is a free software for downloading and converting online videos from many sites like YouTube or Vimeo.

ClipGrab can download from the following sites: YouTube, Clipfish, Collegehumor, Dailymotion, MyVideo, MySpass, Sevenload, Tudou, Vimeo.
Downloaded videos can be converted to the following file formats: WMV, MPEG4, OGG Theora, MP3 (audio only), OGG Vorbis (audio only).

ClipGrab isn’t limited to the sites listed above, because many more sites are supported "unofficially" through the automatic site-recognition of ClipGrab -- just try it!

By the way, ClipGrab can also download HD videos from sites that have support for high definition (e.g. YouTube or Vimeo).

Install clipgrab on ubuntu 11.10

Open the terminal and run the following commands

sudo add-apt-repository ppa:clipgrab-team/ppa

sudo apt-get update

sudo apt-get install clipgrab

Screenshots

 

source: http://www.ubuntugeek.com/how-to-install-clipgrab-on-ubuntu-11-10-oneiric-using-ppa.html