Red refrigerators stocked with free beer have sprung up in public squares around Europe. And, like the Gordian Knot or The Sword in the Stone, many Europeans are trying (and failing) to solve their opening. That's because the fridges only open after scanning and verifying holders of Canadian passports. The fridges are being used as a marketing tool for Canadian beer company, Molson Canadian. The campaign, designed by ad agency Rethink, is meant to celebrate being Canadian, even while abroad.