Kenzo Tange's AMA Building (squatting in the center of this picture, as seen from my office window) imbues Mies Van Der Rohe's austere International Style with shimmery excitement and bold charisma. Constructed in 1990, the 30-story tower is clad in alternating stripes of pale stone and silvery glass that can sparkle in the sun or disappear into the surrounding blue of the sky, depending on your viewing angle. To underscore its rapport with the heavens, it features a four-story hole that fuses the actual sky with its striped reflection.
The building would have a standard rectangular footprint were it not for the slice missing from its southwest corner that leaves a sharp angle pointing vaguely northwest. A 20-story tower pointing the other way was planned for the lot just to the south of the building, but it never got built. Instead, there's a lovely urban park featuring terraced fountains sitting in its place, and it stretches around to fill the slice in the footprint with a pedestrian plaza and a triangular fountain. Unfortunately, the park space is being torn apart to make room for a hotel/condo complex, and the last time I walked by it was surrounded in fencing as its trees were being dug up and hauled away in trucks.
Here's a better picture of AMA Building that I stole from wikipedia since my camera takes crappy pictures through smudgy office windows half a mile away: