Can’t tell you how much I love this campaign by Ogilvy in Brazil.
You take control of a little blue frog with the aim of getting it across the motorway in one piece. However the motorway is real and the traffic is streamed live from a webcam at the location in Sao Paulo.
The game has some nifty object detection to know when a car hits the frog, which is pretty often during rush hour when I played (above)
Try it for yourself http://apps.facebook.com/livefrog/
The campaign is for Allianz, aimed at promoting a safe and healthy lifestyle on the streets.