Pause Home Entertainment, a high-end hi-fi store in Stockholm, has created a business card that turns into a wallet sized, battery-free speaker for your smartphone. The retailer worked with agency Akestam Holst to create the "Pause Cards", which fold outwards to form a pocket-like holder for your phone. The secret is that they are printed on a 330 gram Plike paper that the company claims helps deliver a 17 % boost in volume when the phone is placed inside. The idea is to promote the retailer's customized sound systems.