Print the marker, turn on your webcam and make your own Robin Rhode's "Expression of Joy" painting. BMW commissioned the contemporary artist to make a large-scale painting with a roadster. Rhode affixed paint sprayers to the wheels of a new Z4 to make an automotive paint brush and then drove the car around a giant canvas. This augmented reality app let's users paint by wheels from their personal computers. Also check out the spot, making of video and event from the campaign.