Big Blue Button uses popcorn.js to do a synchronized playback of meeting recordings. This includes audio/video/slides/chat and whiteboard.
I've been asked several times if the recording of Big Blue Button sessions can be edited. And my answer was "soon"! Well, last week in Mozilla Ignite Hackanooga , David Seifried created a prototype that uses popcorn maker to do exactly that!
Here is the video, take a look!
Video of editing a BigBlueButton recording using Popcorn Maker