• 12 Essential Greasemonkey Hacks for YouTube
  
  There's a killer feature that YouTubeYouTube lacks, and you'd love to have it, but it's just not happening? Hold on to your horses; maybe the feature is
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• VideoDownloader :: Mozilla Addons
  Download videos from Youtube, Google, Metacafe, iFilm, Dailymotion... and other 60+ video sites ! And all embedded objects on a webpage (movies, mp3s, flash, quicktime, etc) ! Directly !
  in Software > Mozilla Project > Extensions with download extension firefox video videodownload by 7 users

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