Great Downloader easy to use can convert into multiple file formats. Fast and impressive
Video DownloadHelper - Browser extension to download videos from the Web
StoryMill - Developers and publishers of Mac, Win, and iOS productivity, home and office and writing software such as MacGourmet, Paperless and many more. Based in MN.
youtube-dl-gui - A cross platform front-end GUI of the popular youtube-dl written in wxPython.
BlankPage - Stay motivated to write, and finish your story
Youtube Video and Audio Downloader - Download YouTube videos in all available formats and extract the original audio files.
Manuskript - Open-source tool for writers.