After a disappointing BusinessWeek article about advertising and videogames, I found something more interesting over on News.com. From their article (Link):

An Internet game akin to “Where’s Waldo?” for tracing the movement of dollar bills has helped scientists develop a statistical model for predicting the spread of an epidemic in this country.

Researchers at the University of California at Santa Barbara and the Max Planck Institute for Dynamics and Self Organization have used the Web game “Where’s George?,” which monitors the geographic circulation of dollar bills by their serial numbers, to forecast how a virus would spread from human to human.

The physicists based their research on the idea that like viruses, money is transported by people from place to place.

This sounds familiar.