This new Vietnamese restaurant in Jakjeon South Korea is completely self service allowing it to be so cheap!
Noodles are $3.50 and Dimsum is $5.00. You order what you want at this screen when you first walk in:
You get a ticket with your number on it and when your meal is ready your number shows up on a screen and you go to pick it up at the back of the restaurant.
Because there are no servers the price can be so low but the food is still delicious!
Simple, Cheap and Delicious!