When we were in Hawaii we ate at a sushi place where the plates come past you on a conveyor belt and you grab what you want, though you can also order specific dishes if you don't see them. The biggest challenge was trying to identify something as it moved past you. The color of the plate tells you how much that one costs, ranging from $1.99 to $7.99 or so. They figure the bill by counting the used plates.
The quality was excellent, and they had a lot of cooked fish dishes as well as raw fish ones, so my wife (who like several of you won't eat raw fish) found plenty to eat. Dinner for the 5 of us ran under $100.