MELROSE. You know you’ve entered a great vintage spot when the attitude of the room is as thick as the clothes are hip. Jet Rag is a warehouse of very organized retro-wear for men, women, and children. On Thursdays and Sundays, crowds gather in the parking lot to scavenge ­ on their knees ­ through piles of merchandise during popular $1 rag sales. Between Melrose and Willoughby.