If you're planning to redecorate your flat, have you considered wallpaper that lights up when you touch it? Researchers have demonstrated a pressure-sensitive, light-emitting flexible polymer. They started by mounting an array of organic LEDs, each one turned on and off by its own tiny transistor, behind a flexible sheet of transparent plastic, producing a bendy version of a high-end mobile phone or monitor screen. They then laminated this on a layer of rubber specially designed so that its electrical conductivity increased with pressure. (The photograph shows the finished product.) When a voltage is applied to the back of the rubber, the rubber's high resistance prevents enough current getting through to turn on the transistors, and the LEDs all stay off. If you press on the plastic, however, the pressure passes through the flexible screen and squeezes the rubber behind, allowing more current to reach the transistor underneath your finger and lighting up the LED. The team, which reports its findings online today in Nature Materials, now plans to look at integrating more components into its touch-sensitive electronic skin to produce, for example, computer keyboards built directly into tabletops or televisions laminated straight onto walls.