This past Saturday Improv Everywhere held their sixth MP3 Experiment on Roosevelt Island (just a few days after Charlie Todd's book on the troupe hit stores). There's not much info yet on what exactly went down, but it appears there were inflatable weapons, primary colors, confused residents, synchronized fun and much more (get the mp3 that soundtracked the day here). Katie Sokoler was there to document the whole thing, and IE promises some video in the future.