The Burj Dubai skyscraper (official website), located on Burj Dubai Boulevard, Dubai, United Arab Emirates, is now the World's largest tower. The building, which currently measures about 650 meters, dwarfs the surrounding structures. The Burj Dubai is still under construction, and when finished it will measure 825 meters. (The photo above shows the current and finished building.) The Burj Dubai completion date is scheduled for September 2009.
As you would expect real estate in the world's tallest building will be at a premium, and already the 94th floor has been sold for an estimated $12 million. Expensive, but just imagine the view.