Scientists in Singapore say they\'ve come up with a way to turn almost any surface, such as a whiteboard, a window or even a wooden tabletop, into a touchscreen. Researchers at Nanyang Technological University said the technology is based on the principles of vibration and imaging and can track the movements of multiple fingers and of objects to turn almost any surface into a responsive, touch-sensitive one. By using a few low-cost vibration sensors and a specially developed algorithm, the system can pinpoint the location of a light tap on any surface, and when equipped with low-cost web-cameras it can track the movements of multiple fingers or objects on any surface, a university release reported Wednesday. Since sound waves propagate through matter at a certain speed, it is possible to derive the location of the touch based on when each sensor picks up the signal, research leader Andy Khong said. \"Our innovative system is able to transform surfaces such as wooden tables, aluminum, steel, glass and even plastics into low-cost touch screens,\" he said. \"It means in future, you could play computer games or draw sketches on walls or windows since almost all surfaces can be made touch-sensitive with our system.\"