Keepvid.pro - Download streaming videos online and convert YouTube to Mp3
Softorino YouTube Converter - Download YouTube video & audio. Watch and listen offline
y2mate - Y2mate.
Yout - YouTube to Mp3 Converter
Keepv.id - Keepvid is the best online video downloader. Here you can download videos from 100s websites: Youtube, Facebook, Instagram, Twitter, etc.
You-Get - Command-line utility to download media contents from the web