youtube-dl - A small command-line program to download videos.
4k Video Downloader - 4K Video Downloader is a software program that helps people download video files from sites such as Facebook, YouTube and Dailymotion.
youtube-dl-gui - A cross platform front-end GUI of the popular youtube-dl written in wxPython.
Video DownloadHelper - DownloadHelper is a tool for web content extraction.
ClipGrab - A friendly downloader for YouTube and other sites
Youtube Video and Audio Downloader - Download YouTube videos in all available formats and extract the original audio files.