Great Downloader easy to use can convert into multiple file formats. Fast and impressive
Online video converter - Video conversion tool to convert a video link or file to various formats.
Video DownloadHelper - Browser extension to download videos from the Web
2conv.com - 2conv.com is a simple yet powerful online video converter and downloader that allows you to download any YouTube videos in Mp3 quickly.
youtube-dl-gui - A cross platform front-end GUI of the popular youtube-dl written in wxPython.
y2mate - Y2mate.
Youtube Video and Audio Downloader - Download YouTube videos in all available formats and extract the original audio files.