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
Turn Off the Lights - With a single click on the lamp button, the page will fade to dark.
youtube-dl-gui - A cross platform front-end GUI of the popular youtube-dl written in wxPython.
Magic Actions for YouTube - Magic Actions is an extension that changes the way you’ll watch videos on YouTube.
Youtube Video and Audio Downloader - Download YouTube videos in all available formats and extract the original audio files.