I've always thought that the Burj Al Arab hotel in Dubai was the coolest looking building ever. It's built on a man-made island. They also built a 'neigborhood island' where people build houses to rent or live, but the islands look different. One is shaped like a palm tree, and requires several tons of sand each day to make up for erosion. Anyway, the hotel looks kind of like a giant sail.
Cool, no?