These pictures are two years old. I was seeking for it on the map, following a book rented from my town pubblic library about japanese architecture. The chapter about Tokyo was quite big. The building on this shot is projected by Toyo Ito and somehow watching those pictures again it seems the efforts to find it are worth.
It is called T building, here the link at the Ito`s official web site. It is reachable from daykanyama, then go to the left down to the river, cross the river, and ….sory I don`have the book with me anymore…I am sure somewhere the adress is known. (here somelinks 1, 2, 3
It is an office building. They let me in and get some pictures also of the interior. By those days it might be innovative as well. It was finished in May 1990.