[Quote]:

When a child goes missing or a criminal is on the run, finding the best way to recruit others into helping your cause can mean the difference between life and death.

Now a contest between teams of scientists that hunted down balloons across the nation is revealing what the best strategies might be to mobilize a society.

In the competition, held by the Defense Advanced Research Projects Agency (DARPA), 10 red weather balloons were placed at different locations around the continental United States. Fifty to 100 contending teams were then challenged to be the first to locate them all for a prize of $40,000. According to DARPA, a senior analyst at the National Geospatial Intelligence Agency characterized the problem as impossible using conventional intelligence-gathering methods.

The winner of the contest, a team from the Massachusetts Institute of Technology (MIT), leveraged the power of the World Wide Web to find all the balloons in less than nine hours with the help of nearly 4,400 volunteers recruited from across the country about 36 hours before the competition began. They not only offered prize money to anyone who located a balloon, but also offered money to each go-between who helped relay knowledge about a balloon to MIT.