I’m going to straight copy and paste this from Cube Me. Because I can…
This is the proposed 1.5-billion-square-foot Waterfront City in Dubai by Rem Koolhaas.

This architectural masterpiece is the 1.5-billion-square-foot Waterfront City designed by Rem Koolhaas, an entire self-contained city resting atop an artificial island.

The island will be divided into 25 identical blocks, which will be populated by a mix of tall and squat towers punctuated by more fantastic buildings, like a spiraling 82-story tower, and a 44-story sphere that will be its own mini-city within a mini-city complete with a sprawling network of escalator tubes.
There’s also traditional parks and stuff inside to keep it a little more earthly, but every new gargantuan development like this makes us wonder just how far Dubai will push it next.

And if you want to read more, the New York Times has all the info your little heart desires.