If you are a Firefox user then downloading videos from video sharing sites like YouTube, Google Video, MySpace, Metacafe, Dailymotion, Veoh, Blip.tv and Megavideo is easy for you.All you have to do is to install this excellent Firefox addon called “NetVideoHunter “
NetVideoHunter is a Firefox add-on which allows you to download videos and music from all YouTube-like video-sharing sites.
It is very easy to use ,once you have installed the add-on you will be able to see a tiny blue icon at your status bar. Now simply go to a video sharing site(youtube) where you want to download the video , While the video is loading you will see a number next to the blue button which will indicate that the video is available for download, Click the blue button to open the NetVideoHunter window then click the download button and save the video file.
More information: NetVideoHunter
Download : NetVideoHunter