Check out the 660 ton "mass damper" inside of Taipei's 101 skyscraper. This enormous metal ball is suspended in between the 88th and 92nd floors, and is 18 feet in diameter. Designed to act as a pendulum, staying still or swaying against any movement of the building, it helps keep the overall center of gravity and structural integrity in a safe operating window.

Following a 6.8 magnitude earthquake in Taipei, the mass damper can be seen doing its thing and swaying side to side in controlled motions while the building shakes. As skyscraper 101 is a 1,667-foot tall building just a football field's length from a fault line, this mass damper is essential in maintaining the safety of the building, and did so once again here. Almost 150 people were injured following the recent earthquake, but thanks to this giant mettle ball, the many people inside and around skyscraper 101 are not among them. It truly is a marvel of engineering.