Some customers of the Sacramento Municipal Utility are getting frowning faces in the mail for their energy use. Using a novel concept to get their customers to reduce electrical use, the company started an experiment of selecting customers and showing them how their energy usage ranked compared to their neighbors with similar-sized homes. Doing well (using less energy than the neighbors) earned a stamp of one or two smiley faces while using a lot of energy earned frowning faces. After six months, a follow-up study found the selected customers reduced energy use by 2 percent more than those who got standard statements. Now the idea is being adopted by 10 other metropolitan areas, including Chicago and Seattle.