Improv Everywhere has done a number of clever performance projects in NYC, including the Central Station and Home Depot freeze/slo mo actions, but this may be their best yet, IMO. They got 15 pairs of identical twins to ride the subway, sit across from each other, and mimic each others actions on the train. Talk about a mindf*%k if you happened to step onto that car. Check out this video to see for yourself. Great idea!