Firefox: If you’d like to save a video you’ve found on a popular streaming video site, NetVideoHunter is a handy Firefox extension that makes that download a snap.
Most extensions and add-ons enabling video downloading usually place a single link by the Flash video box on certain sites, letting you download the file you’re currently watching. NetVideoHunter places a small icon in the lower right corner of your browser, tracking the videos you’ve watched.
Clicking on that icon will bring up a list of videos, including the current one you’re watching. From that list you can download or play the files. The ability to grab previously viewed videos is rather handy if you’ve decided, after tunneling through a YouTube chain, that you’d like a copy of that video three clicks back. It works on nearly any video sharing site including YouTube, Google Video, Metacafe and Dailymotion.
NetVideoHunter is free and works wherever Firefox does.
YouTube has made it easy for anyone to easily download clips as MP4 video files, if a creator allows it, as well as purchase the videos you want to bring with you.