Yay for Odaiba! I went this weekend with the "go nin" 五人. Apparently Odaiba is some sort of "dating spot"- whenever I tell a Japanese person I am going or went to Odaiba, they always ask if it is/was a date.
This is the "Fuji Television Building" which is soooo cooool! Total tourist trap- most of it seems to be filled with tacky souvenier shops selling figurines of TV show actors (the building apparently produces many TV shows here...?)- but I love the architecture. You can pay 500Y to ride the elevator up into the "ball", but I figured that was lame, since I only really like looking AT the ball, not being IN the ball. Besides, you can get much higher views for free from the Tocho in Shinjuku.