Ant Video Downloader - Addon for Mozilla Firefox to download videos from video websites
Video DownloadHelper - Browser extension to download videos from the Web
ByClick Downloader - ByClick Downloader (Former YouTube By Click) is a video downloader software for Windows. (Former YouTube By Click) Supported sites: YouTube, Dailymotion, Vimeo, Facebook, Instagram, Twitter, Pinterest and +40 site
FlashGot - FlashGot is a browser extension for Mozilla Firefox that is designed to make it easy to download a whole batch of files in one go. The extension is open source and free to use, but it is no longer compatible with the most recent version of Firefox.
deturl.com - How to download YouTube videos for fair rights use. No software required. Support for DailyMotion, Vimeo, and FaceBook. Save as MP3 music.
ClipGrab - A friendly downloader for YouTube and other sites