lee1 writes "A law in the US that is due to take effect in 2012 mandates such tough efficiency standards for lightbulbs that it has been assumed, until recently, that it would kill off the incandescent bulb. Instead, the law has become a case study of the way government regulation can inspire technical innovation. For example, new incandescent technology from Philips that seals the traditional filament inside a small capsule (which itself is contained within the familiar bulb). The capsule has a coating that reflects heat back to the filament, where it is partially converted to light. The sophisticated ($5.00) bulbs are about 30% more efficient than the old-fashioned ($0.25) kind, and should last about three times as long. So they are less economical than compact fluorescents, but should emit a more pleasing spectrum, not contain mercury, and, one supposes, present the utility company with a more desirable power factor."