Great Downloader easy to use can convert into multiple file formats. Fast and impressive
Enhancer for YouTube - Tons of features to improve your user experience on YouTube™!
Video DownloadHelper - Browser extension to download videos from the Web
ImprovedTube - Allows you to improve and enhance Youtube visually or enable dozens of new features permanently or...
youtube-dl-gui - A cross platform front-end GUI of the popular youtube-dl written in wxPython.
Iridium by ParticleCore - Iridium is an extension built to improve the user experience on the new YouTube Material layout.
Youtube Video and Audio Downloader - Download YouTube videos in all available formats and extract the original audio files.