The film "Daybreakers" did a promotion which used this technique in late 2009. The film's premise is that a vampire virus has swept through humanity, converting most people to vampires and leaving only a few surviving humans. These remaining humans are hunted and captured to provide blood for the rapidly starving vampires.

The ad was a site http://www.capturehumans.com , which pulled your Facebook picture and pictures of your friends. The site then showed a short video on the origins of the vampiric plague, with you as Patient Zero. Your friends showed up as other early vampires or as humans to capture.

The site isn't loading for me now, but this description gives this idea: http://www.movieviral.com/2009/12/15/daybreakers-gets-a-vira...