I actually don't like global queueing for the simple reason that I have to keep moving. In a local queue, I can stop and ignore the world for a minute. My fav

I actually don't like global queueing for the simple reason that I have to keep moving. In a local queue, I can stop and ignore the world for a minute. My favorite solution is that adopted by my local Trader Joe's. They use local queues, but somehow seem to magically always have just enough checkouts open that at most one person is waiting in each queue. Further, the queues are not separated from each other by barriers, so when a cashier empties their queue (a common occurrence), they can steal customers from neighboring queues. In fact this system works so well that I don't think I've ever had to finish waiting for the person ahead of me in my chosen queue. Almost invariably, either there is a free register, or another cashier steals me before I reach the head of my queue. I think this system is enabled partly by the fact that Trader Joe's are almost always small enough that workers can be summoned to cashier duty from anywhere in the store in a matter of seconds. Traditional supermarkets are too large to be able to react so quickly to workload variance, leading them to rely on deep queues to keep cashiers busy. (Not all Trader Joe's are blessed with this system. There is one in Boston, the smallest TJ's in the nation, which, owing to its size, must resort to a global queue which, at peak hours, snakes its way through all aisles of the store such that the only means of shopping is to first get in the checkout line, and then to add things to your basket as you slowly make your way to the checkout. I suppose in some sardonic sense this is the most efficient of all systems, if you are purchasing items from all sections of the store anyway.)