Incidentally, I explained this exact concept to a few friends who I talk to about my project, except I used Pat & Oscar's! You order and they give you a number, and you go sit down. Then when your order is ready, they come to you by finding the table with your number on it. A benefit to this analogy is that you can have multiple outstanding "orders", simply by having multiple numbers on your table.
I've been meaning to write a post about how I plan on using this, I just haven't felt motivated. Maybe I will now!