At night, various makeshift stalls pop up, with vendors squatting over tables and fabric on the ground and selling everything imaginable. It might be a grandma selling a piece of paper with bobby pins for 1 RMB, a man selling handheld sewing machines, or a stand selling toys such as plastic koi fish that swim in circles on the floor.
Pop-up shops around the metro stations, catering to the young and tech-savvy, can have genuinely cool finds, with anything handmade and considered unique being the motherlode. Cool little bags and boxes are a favorite of mine. Whatever you find, it's sure to be cheap—and you might find that shopping the impromptu flea markets is strangely addictive.