Taipei 101's 730-ton damper ball

The world's tallest building is the 1667-foot Taipei 101 in Taiwan. One of its features is a 730-ton steel ball, made of 41 steel plates, that acts as a damper against swaying motions of the skyscraper due to wind.

On May 12, 2008, the damper, which sits between the 87th and 89th floors of the building, got a workout from the earthquakes that hit China's Sichuan province. And a YouTube user was there to get footage:



(Via deputydog, which has more information about the damper. Hat tip to Dan Noland on the SKEPTIC mailing list.)