Normally the models in BMW's art car line -- sixteen and counting -- get their body panels splashed up with designs by the who's who of the art world. BMW has decided to switch up the concept for a commercial for the new Z4; instead of the car being the canvas, the Z4 paints a canvas. Guided by modern artist Robin Rhode and a team of technicians, the Z4 is rigged up with machines that spray paint from the wheels, with everything captured on film by director Jake Scott, Ridley's son. The tire prints in all kinds of hues are laid down on an enormous white canvas, and the result is called "An Expression of Joy." You can check out the press release after the jump, the high-res gallery of images below, and Wallpaper magazine has behind the scenes video. If you like what you see, you might even be able to buy a slice of it in due time.