The clubs downtown have closed, but you're not ready to go home just yet. After years of chowing on the delightful Del Taco (and it is delightful) or having chili on your scrambled eggs (still delicious), your palate has become more demanding. What you need is a sandwich and a milkshake. Not only does Coffee Cartel make shakes from scratch, the late-night bohemia packs a lot of tasty stuff between two slices of fresh bread. And you won't have to eat alone: The Cartel, open around the clock, draws a fine and varied crowd at nearly any hour. Whether you're enjoying ice cream at 5 a.m. when you can't sleep, a smoothie after an afternoon jog or a coffee-liquor drink after a late movie at the Chase, it's fun to fantasize that a time may yet come when the rest of the city catches up to this joint, lively whether it's dark or day, at the corner of Maryland and Euclid.