The Mori Modern Art Museum, which resides in the Roppongi Hills Tower, is currently curating a show called City Models Exhibition - Tokyo Perspective. The exhibit looks really cool. It features a 1/1000th scale model of Tokyo (designed by Mamoru Ishii, who created Ghost In a Shell), which goes hand-in-hand with the newly released Tokyo Scanner film, a DVD that collects tons of shots of the city.
I would love to see the exhibit, as it is quite difficult to see the whole city from so many different angles. And judging by the picture, it looks rather detailed.
They have also made models of NYC and Shanghai, which I am sure are equally spectacular. Here is a little walk-through of how the models were made ... intense!