List of Tools and websites which are useful for downloading videos from online video sharing sites like youtube , Myspace, Facebook , Google Video

DownloadHelper 2.6.1 is very good firefox addon which is used for downloading Videos from video sharing sites
Click here to Download

FLV Downloader is a free utility for downloading Videos which are in the FLV (Flash)format from all video sharing sites at high speed. Click here to Download

iDesktop.tv and Vixy.net are the websites which are useful for downloading videos from sites like Youtube , MySpace , Google Video , Facebook and similar sites