I agree with Masaki, don't miss the fish markets - they're huge. The most fascinating thing I remember, except for the little washing machine thingies that they drive around, was there is absolutely no odour at all from the fish. I saw the auctioning and although frantic and interesting, don't worry if you miss it as the whole place is really worth seeing. I saw varieties of seafood I didn't know existed.
We saw the Edo Tokyo museum and enjoyed it. The building itself is worth seeing.
