The genius folks over at Cucusoft have developed a killer app for windows that allows you to download YouTube videos and save them in many formats including MP3! If you are a media collector like me with a few dozen of your favorite music videos on your hard drive, this works with the latest YouTube scripts! Works great when creating a DVD of you favorite YouTube videos for play in your living room, portable DVD player on long trips or just for offline play on your computer.
It's free, but you do have to submit your email address for a registration key; the process is very fast and easy. For more info and file formats visit http://www.youtube2mp3converter.org