Yodobashi-Akiba, Akibahara district, Tokyo, Japan.
From the Sushi Boat Restaurant on the eighth floor of Yodobashi Akiba. The concept of this Restaurant is that you get charged per plate that you grab off the boat. Each plate has a different price point depending on the plate's color. At the end of the meal, the waitress will wave a wand down the tower of plates you've accumulated, presumably reading the embedded RFID on the bottom of each plate. This wand will give you the total of your bill, along with a breakdown of how many plates of sushi you had per price category.
Each trip for both of us cost around $30-40 USD.
February 2017.