Here's an unconvential promo. In Great Britain this new Chevy Captiva was coated with that silvery scatch card material with thousands of scratch-and-win panels beneath. People were invited to use one of the many pennies on the ground to try and reveal the You Win! square. The person who found it, won the car. Let's just hope it wasn't too scratched up. There really doesn't seem to be much of a brand message here but it's sure an innovative way to get people to see the car and engage with it (perhaps take a peek through the window to see the plush interior.) In the words of P.T. Barnum (master of marketing), "A sucker is born every minute." Don't know the agency.
Thanks to jonathan for the tip via gizmodo