Odaiba is a waterfront area of big shopping malls, game centers, exhibition halls, and museums. It's a neat place to get a different view point of Tokyo from across the Bay while checking out interesting stuff - top draws include the Odaiba Ferris Wheel, the Museum of Emerging Science, the Maritime Museum, and Sega World. Busy on weekends, it is much quieter on weekdays. Get there either by the Yurikome monorail from Shimbashi, or by ferry from Hinode pier.