An easy trick to save YouTube videos to your comp.
In the address bar add OK between www. and youtube of the addy.
Original addy is "http://www.youtube.com/watch?v=c42czVwDRl8"]YouTube- 1264735178.mov
Save addy is http://www.OKyoutube.com/watch?v=c42czVwDRl8
In FireFox it will bring up a prompt to save.
It will play back in Windows Media Player.