This is Drone 100, a collaboration between Intel and Ars Electronica Futurelab starring 100 aerial drones performing a choreographed dance routine to an orchestra performance. It managed to secure the Guinness World Record for most unmanned aerial vehicles flown simultaneously, apparently because my roommate and I dumping two boxes of paper airplanes off the roof of our apartment building didn't count, even though it should have. Now I don't want to point any fingers, but I suspect sexual favors were exchanged.
Keep going for the video.
Thanks to Donald B, who is more than a little disappointed nobody tried to shoot fireworks at them.