"MIT wins $40,000 prize in nationwide balloon-hunt contest"
CNN:
A team from the Massachusetts Institute of Technology won $40,000 in a high-tech scavenger hunt on Saturday by discovering the location of 10 red weather balloons.
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This contest was designed to test the way social networking and lesser-known Web-based techniques can help accomplish a large-scale, time-critical task.
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"We're giving $2,000 per balloon to the first person to send us the correct coordinates, but that's not all -- we're also giving $1,000 to the person who invited them. Then we're giving $500 whoever invited the inviter, and $250 to whoever invited them, and so on..." it said.