Here's an eight-minute video that shows you a grandiose idea somebody dreamed up: building a 3000-foot-tall pyramid in Tokyo Bay. This megacity would be so tall, and would have such tremendous volume that 24 80-story skyscrapers could be suspended within, and people would travel inside it via the tubes that are also supporting the enormous structure. It's extreme engineering, indeed.

So, the Japanese have decided the next 9-11 will be third impact...

Gizmodo UK : Gigantic 3000-foot Pyramid Proposed for Tokyo Bay