Yo! Tekko-ya in Odaiba is an unsung little ramen place, but I've eaten at many, many ramen places in Tokyo and around the world that are both famous internationally and among locals, and I've never had better. That's the one place I make sure to go to on every trip, and I've been going for the last 10 years or so. It's pretty far out of the way, which is probably why it's not more famous, but Odaiba's a fun place to visit anyway for other reasons, so you should go there if you visit for anything else.

Yo! Tekko-ya is a chain with other locations, but like a lot of small chains in Japan, it's really a chain in name only. I've eaten at one or two of the other locations and they were 100% different. The one in Odaiba is the one you have to go to.

You may as well eat sushi at either Daiwa sushi or Sushi Dai at Tsukiji Fish Market. I'm sure somebody here will say they're overrated but I trust my wife, who's from Tokyo, and she was almost literally knocked to the floor by several of the pieces she was served. She was talking about it for weeks afterwards. To be honest I don't 100% remember which one we went to, but I think it was Daiwa. They are both right next to each other and both typically have long lines, but they move quickly. You sit down, you eat, you leave. So you shouldn't be waiting too long.