Researchers develop an environmentally friendly light bulb

"(...) a team of researchers has devised a light bulb that is not only much more energy-efficient—it is also expected to last longer than the devices into which it is inserted. (...) The resulting light is bright, and the process is energy-efficient. Indeed, whereas traditional light bulbs emit just 5% of their energy as light, and fluorescent tubes about 15%, the Ceravision lamp has an efficiency greater than 50%. Because the lamp has no filament, the scientists who developed it think it will last for thousands of hours of use—in other words, for decades. (...)"

Source: The Economist
More info: http://www.ceravision.com/technology-introduction-2.html