Looking out the window during a long car trip becomes an interactive adventure with a new GPS-based game developed by The Interactive Institute in Stockholm, Sweden. The Backseat Playground uses GPS to turn passing sights such as forests, buildings, and rivers into locations for in-game characters and events, reports New Scientist magazine. Backseat Playground consists of a GPS receiver, a handheld computer, and headphones connected to a laptop in the trunk of the car.