If Miami is a global crossroad, then Mary's, which never closes, is a crossroad within a crossroad. Here, in the middle of the night, you can find regular folks doing their laundry while munching on a croqueta or some drunk young professional from the Grove grabbing a late-night snack. During the day, families pop in for an armful of cold drinks while someone else stops in for a quick Cuban sandwich on a 15-minute break from work. The blue awning and hum of the traffic offers a special kind of solace, a moment of relaxation, even as construction thumps all around and a pair of tires occasionally shriek. Never fret. With a medianoche ($5) in hand, all of the concerns about what you may have done earlier that night, or what you might have to slog through in a haze in the day ahead slip away.