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Olympics fountain

Olympic rings with cycle powered fountains are installed on The River Thames at Greenwich on August 1, 2012 in Greenwich, England. (Photo by Peter Macdiarmid/Getty Images)

Olympics Bicycles power Olympics fountain

Visitors to The Old Royal Naval College in Greenwich, England can use harnessed bicycles to

power fountains during the day and help illuminate the giant Olympic

rings at night. (Aug. 1)