The quadcopters make a dramatic entrance with smoke and lights, and then proceed to perform. The musical instruments include the keyboard, drums, maracas and a cymbal. A guitar built from a couch frame is also played by the quadcopters flying over the guitar strings and dragging wires across them. The quadcopters play the key board by hovering over various landing pads each of which is attached to the keyboard keys.
Their research group has some amazing videos of quadrotors in coordinated flight, and quadrotors working together to perform a coordinated construction task. The GRASP lab is involved in numerous other projects that are worth checking out.
Here is a video of quadrotors in coordinated flight: