Interface, Interaction and User Experience Design Puzzle Facade Interactive experience by Javier Lloret Puzzle Facade transforms the Ars Electronica Center (Linz, Austria) into a giant Rubik's cube. The participant interacts with the interface-cube. This cube holds electronic components to keep track of rotation and orientation. This data is sent to a computer with a software that changes the lights and color of the building in correlation to the handheld interface-cube. The strong spatial connection between the architecture (AEC building), the referred object (Rubik's cube) and the designed tangible interface (interface-cube) enhances the site-specific aspect of the project.