Mac owners, download MacX Video Converter Pro for free.
MacX Video Converter Pro lets you download YouTube videos, convert among all HD and general video formats for playback on iOS devices, mobile phones, PSP, etc. Use the license code in the SN.text found in the zip file to activate.
This version has no tech support and upgrade service though.
Download the application before September 20, 2011 at http://www.macxdvd.com/special-offer/back-to-school-2011.htm