Sync videos
Have you seen the insane amount of cameras recording live events from different angles? Nothing is being done with these videos.
You sync videos in pairs.
First you choose two points of view of the same thing and take note of their Youtube video IDs.
Then you place them in the Builder. There you can mark a common point in both videos.
After that, Multitube should figure out a way to play them perfectly in sync.
Knock yourself out. Be warned that it is in an extremely alpha stage, it is unstable and will probably not play stuff in sync unless you click seek all three or more times.
If anyway you want to try it out, go to: http://mt.pedrovalente.com/mt.html