Al writes "A super-cheap, thin and flexible touch interface developed by researchers at New York University and could be used to add touch sensing to all sorts of gadgets and devices. It measures a change in electrical resistance when a person or object applies different pressure. The "Inexpensive Multi-Touch Pressure Acquisition Devices (IMPAD)" consists of two sheets of plastic containing parallel lines of electrodes. The sheets are arranged so that the electrodes cross, creating a grid and each intersection acts as a pressure sensor. The sheets are also covered with a layer of force-sensitive resistor (FSR) ink, a type of ink that has microscopic bumps on its surface. So, when something coated in the ink is pressed, the bumps move together and touch, conducting electricity."