Paint by powerslide with this BMW Z4 app
BMW Z4: An Expression of Joy Lite is a free iPhone/iPod Touch app by Artificial Life, Inc. that allows users to get behind the virtual wheel of a customizable 2009 BMW Z4 Roadster.

Recently, BMW put a new spin on the art car concept by making the new Z4 Roadster the brush instead of the canvas. Essentially, the artist took a Z4, dunked its tires into red, blue, and yellow paint, and proceeded to whip donuts on a 200 by 100 foot canvas. Now, that's my kind of fine art!
Well, now there's an app for that. (Sorry, I couldn't help it!)
BMW Z4: An Expression of Joy Lite is a free iPhone/iPod Touch app by Artificial Life that lets people get behind the virtual wheel of a customizable 2009 BMW Z4 Roadster to create works of art. Users can choose paint color on the fly on a per wheel basis (a luxury the original artist was not afforded).
The accelerometer-based steering varies in responsiveness from nearly unresponsive in bird's-eye view to quite nimble in the first-person view. At least you're given discrete gas and brake buttons, which is more than I can say about most iPhone driving games. Players can even disable the traction control for epic powerslides--which is always fun, even on tiny screens.
Once you're done, you can save your masterpiece to set as your wallpaper or for e-mailing to friends.
BMW Z4: An Expression of Joy Lite is available for free in the Apple iTunes store. According to the programmers' Web site, a full version is coming soon, but it doesn't outline what features it will add.