Possibly the most beautiful thing I've ever seen
First, just go watch, before I spoil it by overanalyzing it.
This just about breaks my heart it’s so beautiful. All these people scattered around the world, alone in their living rooms with their webcams or cellphone cameras, unwittingly taking part in a concert that was just waiting for someone to come along and put the pieces together in the right order.
It makes the whole world feel more real. It’s all music, just waiting for the pieces to be put together in the right order.
(Apparently the site is not always available; there’s an unofficial mirror here. Both sites have credits links to all the original youtube clips from which this was pieced together. If you don’t get as completely sucked in as I did, make sure you at least watch #1 and #5.)