Odaiba is a waterfront area to the east of Tokyo city, its a reclaimed land island and a popular spot, especially on the weekends for tourists and locals alike.
I’ve been there a few times, as there is a “Bills” restaurant there and every now and again I crave scrambled eggs for breakfast, so if in Tokyo I hop onto the Yurikamome line and head to there for the morning.
The area has lots of attractions and things to do. Shopping areas, park areas, museums, restaurants and even its very own statue of liberty. The 12m high statue is a replica of the Statue of Liberty from Paris brought to Japan 1998 to celebrate “The French Year in Japan.”
The Decks complex houses a Legoland and a Madame Tussauds amongst many other attractions.
You can catch the ferry back across to Tokyo, coming into Hinode pier for a few hundred yen. Some great views of Tokyo & the Rainbow bridge from the water.