If there were to be a "Toyko Ring", I would love to see it based on the Shoutokou, or the highway system that runs thru Tokyo. Relatively un known, but it's quite on par with the Nordeschleife. Only problem is that you people woud get quite bored with the Wangang expressway (if you have the horsepower you can reach speeds of more than 270 MPH) because it is quite long and quite straight.