Mattress firm Mattress Firm is almost all snuggled into its new Linden Square location. The sleep spot has taken over the former Sleepy's location at 165 Linden St. According to the Wall Street Journal in November, "Mattress Firm Holding Corp. is the largest U.S. specialty mattress retailer…it agreed to buy second-place Sleepy's for $780 million, in a deal aimed at expanding the company's presence in the fragmented retail bedding market."