Great Downloader easy to use can convert into multiple file formats. Fast and impressive
Add Music to Video App - Add Music to Video is an intelligent video editing application that helps you make your everyday videos more exciting by adding background voice-over or music to your video.
Video DownloadHelper - Browser extension to download videos from the Web
Video Merger - Video Merger is a powerful video-merging application, allows you to merge your favorite videos into a single large video by adding background music of your choice.
youtube-dl-gui - A cross platform front-end GUI of the popular youtube-dl written in wxPython.
ROLR - Act out your favorite movies with friends
Youtube Video and Audio Downloader - Download YouTube videos in all available formats and extract the original audio files.