Taipei 101 (Taipei, Taiwan)
Taiwan is one of the most dangerous spots on the planet for a skyscraper. The island is rocked by 20 earthquakes each month, and is vulnerable to typhoons' vicious 200-mph winds. (Typhoon Talim, for example, killed 150 people and caused $1.5 billion in damage to the island in 2005.) But with a shortage of developable land in Taiwan, the only way to build profitably is to go up. The need to combine height with protection from natural disasters resulted in Taipei 101. The 3-year-old office tower, which measures 1,670.68 feet in height from the ground to the tip of its spire, is the world's tallest building, and also possibly the most stable. In the building's core, between the 88th and 92nd floors, engineers have suspended a 730-ton steel sphere that essentially acts as a giant pendulum, swaying as much as 18 inches off its axis to absorb the force of storms and quakes. Additionally, the building's frame is designed to be strong and flexible enough to withstand massive amounts of energy, with two dozen vertical columns to provide support and a steel web wrapped around the exterior. Every eight floors, outrigger trusses connect the core columns to those on the exterior, distributing the building's load. For good measure, the skyscraper is equipped with its own diesel-powered generators capable of keeping the lights and air conditioning on, even in the midst of a cataclysm. But at least one scientist thinks that Taipei 101's sheer massiveness may pose a problem. Cheng-Horug Lin, a seismologist at Taipei's Institute of Earth Sciences, has advanced the bizarre theory that the building's 705,000-ton weight may be stressing underground earthquake faults, and thus actually causes quakes to occur.