According to a study conducted by the plastics manufacturer Nalgene, Sacramento leads the nation in the use of energy-efficient light bulbs. The study, called America's Least Wasteful Cities, questioned 3,750 people living in America's 25 largest cities. Participants were asked about how much garbage their households generated, their shopping and transportation habits, and other sustainable behaviors. Mayor Kevin Johnson said, "I'm proud that Sacramento tops the list in using energy-efficient light bulbs but there's still plenty more work to be done to move us up the list in other categories. Particularly with the challenging economic conditions we're in, we should not reduce our effo