DamnVid

DamnVid is a downloads manager that's compatible with dozens of different websites, including YouTube, Dailymotion, Veoh, Metacafe, and Vimeo.

Its most interesting feature lets you convert videos to different formats while you're downloading them, so you can have the video on your hard drive, and in the format you need as soon as it's downloaded.

The application works quite quickly, and doesn't take too many resources for what it does, so almost any kind of computer can handle it without much hassle.

DamnVid is a great tool for anyone who wants to download his or her favorite videos and convert them to a different format instantly.