Most of you have ever wanted to keep a loved one video on facebook, youtube or dailymotion, the easiest way for 'stealing' or download a video from facebook is downloadhelper if not the most effective tool that I recommend, whether for facebook, youtube, dailymotion or any other video site is: downloadhelper addon or plugin that installs with firefox .
DownloadHelper is a Firefox extension for web content extraction. His goal is to capture (and convert) videos and images from many sites, its use is easy, you go to the link of the video that you like, you right-click the page you go to downloadhelper => media => and choose the name of your movie (extension. flv or mp4) to the video hosted on facebook you have a name not clear (exp: 103342946376274_13501.mp4) if not for youtube or dailymotion you find a title similar to the video.
The prerequisites for using download helper: