Nico Nico Douga Downloader - Download anime videos, audio music mp3, thumbnail images, manga from nicovideo.jp
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.
Download Surgeon - Download Surgeon is an audio and video downloader that can download A/V from YouTube and 1000's of other sites. 100% Money Back Guarantee. BBB Online Member.
Video DownloadHelper - Browser extension to download videos from the Web
Youtube Video and Audio Downloader - Download YouTube videos in all available formats and extract the original audio files.
ClipGrab - A friendly downloader for YouTube and other sites