3,500 Person Flash Mob Synchronized By MP3 File
Shareable writes "Improv Everywhere's latest mission was a 'mp3 experiment' in which 3500 strangers downloaded an mp3 file, assembled in a park, pressed play simultaneously, and by following the directions on the mp3, acted out a mass synchronized ballet of movement and light."
Here is Improv Everywhere's write up of the event: http://improveverywhere.com/2011/07/25/the-mp3-experiment-eight/