Today's power-hungry laptops can run for only a few hours before they've eaten their way through a full battery. The main culprit is the display, which must be powered to overcome ambient light. That could be set to change, courtesy of a light-harvesting screen developed by Freelight Systems Ltd. One of the directors of Freelight, which is a spin-off of Napier University, saw the potential of a light-gathering plastic. Fibers extruded from the plastic gather light along their length and emit it at their tips. The monitor requires a liquid crystal display to turn the fibers on and off, so it is not quite a free lunch, but the effect boosts the brightness of the spots they produce by 30 percent over ambient conditions.