Kate Spade is exploring new retail concepts with "Saturday," its recently launched "weekender" line. From now until July 7, passersby can stop at 154 Spring Street, 7 West 18th Street, 175 Orchard Street or 30 Gansevoort Street to browse and purchase goods from the line, which for now is only sold online in the U.S. and in brick-and-mortar stores in Japan. Orders will be delivered free by courier service within one hour in Manhattan and parts of Brooklyn. Couriers will even wait while customers try on the clothes they've ordered, and only take payment (via PayPal) for the items they decide to keep.

"We're redefining what it means to window shop," says Healey Cypher, head of retail innovation at eBay, which partnered with Kate Spade Saturday on the initiative. "There's no inventory and no [store associate]."