The swiss army knife of lossless video/audio editing
...Or you can add a music or subtitle track to your video without needing to encode. Everything is extremely fast because it does an almost direct data copy, fueled by the awesome FFmpeg which does all the grunt work. Lossless merge/concatenation of arbitrary files (with identical codecs parameters, e.g. from the same camera). Lossless stream editing: Combine arbitrary tracks from multiple files (ex. add music or subtitle track to a video file).
Online music publishing system that enables mass collaboration among registered users. Users will submit pieces of work for others to add and edit to create other renditions of the work.