Target market is the high-powered executive/creative-class knowledge worker who really misses the simple times - when they were in their early-20s, pulling espresso in a grungy indie coffee haus. Or anyone else who wants to play barista - I'm sure there are other scenarios that fit.

This can be run in a really small, narrow space, provided there are exits at front and back, and with only two employees on duty at any time (a cashier and a dishwasher).

The cashier provides you with a pitcher of milk, a portafilter, a paper cup if necessary ($0.15 extra) and a rag.

You walk back to one of 8 or 12 single group espresso machines, each with its own grinder, set up like voting booths or urinals against the wall with dividers between them.

After making your drink, you wipe down the space with the rag, put all the hardware into a bus tray, and escape to a better life.