Architect Norman Foster has a track record of getting breathtaking structures built: He tossed a footbridge across London's Thames River and stuck a huge glass dome on top of Berlin's Reichstag. But his proposed Crystal Island project takes his ingenuity to a whole new scale.

On the banks of the Moscow River, Crystal Island would rise as high as the Empire State Building but spread out like a tent, covering the Nagatino peninsula with a massive structure containing apartments, hotel rooms, shops, museums, theaters, and cinemas. To increase energy efficiency, the entire building would have an outer "skin" of louvered panels that could be closed to keep out the harsh Russian winter and opened to let in cooling summer breezes.