If you shake a can of Guinness, you will hear a small plastic ball rattling inside. This is called a 'widget.' Patented by Guinness in 1988, the widget is a hollow plastic sphere with a tiny hole in it. During the canning process, nitrogen and a small amount of beer are forced into the widget under pressure. When the can is opened, the pressure inside drops instantly, causing the compressed gas and beer to jet out through the tiny hole. This agitation causes the dissolved nitrogen in the beer to form millions of tiny bubbles, creating the thick, creamy 'draught' head that Guinness is famous for. This invention was so successful it won the Queen's Award for Technological Achievement in 1991, beating out many high-tech electronics companies.