Fastest Video Downloader is a free extension that allows you downloading online videos to your PC. It supports wide range of popular websites like YouTube, Vimeo, Vevo, Facebook, Dailymotion, and over 10,000 other websites. This add-on can neatly grab any video streaming in the original quality. Following formats are available AVI, MKV, WMV, 3GP, for iPhone, iPod, PSP, Android. Just install the extension and enjoy it with no fees, no limitations and no sign up requirments.
Note that available options depend on quality of uploaded video and your device.