Oh my, am I ever hoping this project gets off the ground. :3 As many of you may know, I'm a sucker for Archology projects. I think they're a great way of efficiently using land, and easing urban sprawl. Personally I think a handful of mega cities within large buildings would be far better than spreading roads and suburbs over every usable chunk of land on the planet.
For a few years now, engineers in Tokyo have been designing this little gem, called Sky City. There seems to be a multitude of potential uses for the design, either as single towers, or big conjoined units with other services tied in. Each tower is a full kilometer in height, 400m wide at the base, and 160m wide at the top.
They hope to have 35,000 residents or more living in each tower, plus a daily workforce of over 100,000 per tower. So in theory, quite a lot of the people working there could live there too. More if they add more residences nearby, or around the towers.
That's the base layout of a single tower. Note how every floor-like segment of the tower actually creates a large interior bowl. The inside of each bowl will be used for green spaces and indoor open-air park systems. Along the rim of each bowl will be a monorail system, used to get people around the structure to certain key walkways and elevators. They appear to have devised a system where there are high speed elevators that only go from zone to zone, so to speak, connecting all of the stations together and whatnot. Then within each zone of the tower, there are regular elevators and stairs to go up and down accordingly.
Here's the general design of a completely linked structure. At the top will be more residences, businesses, industry, and whatever else they need to pack in there. Suspended lower down is a combination sports stadium, pools, etc.
Here's an interior view of the open air parks.
I don't know about you lot, but I'd sure as hell live in a place like this. :3 I believe there was a show about this design once, on Discovery's Extreme Engineering program. Look it up! I know I will. :D If you could live, work, and play all in the same mega structure, it would really cut down your commute time everywhere. You could spend more time living your life, and less in a car taking hours to go places within a busy city.