Beneath more than 200 T-shirts hanging from the rafters of shirtmaker Threadless’s cavernous Chicago headquarters, workers play Ping-Pong, billiards, foosball, or Big Buck Hunter. Chief Executive Officer Tom Ryan’s French bulldog Lola, wearing perhaps the only collar on the premises, roams freely. “We believe in having a fun space,” Ryan says.

Shoppers can visit the office showroom and shop online for one of Threadless’s custom T-shirts.