CONV. - Convert YouTube video to MP3, GIF or MP4
Video DownloadHelper - Browser extension to download videos from the Web
Downie - Video download for OS X. Downie supports at this moment over 1,000 different sites.
Flash Video Downloader - Flash Video Downloader is a popular extension for Google Chrome browser for downloading wide range of files over the internet.
Yout - YouTube to Mp3 Converter
FastestTube - Youtube fastesttube downloader will make your internet expirience faster harder beter stronger.How to merge video and audio .