Are you using CFLs -- compact fluorescent lamps/lightbulbs? If not, read this -- pronto! And if you're one of the millions who've made the switch to super-efficient, low-energy bulbs, here's a tip: You can save even more energy by installing dimming swtiches in rooms where it's appropriate -- the dining room and den, for instance. That way, the bulbs don't have to be on full-force whenever they're turned on, though you can choose to have them on high when you need more light.

Doing this could potentially save quite a bit of energy. For example, if you reduce your lights by 25%, you save 25% more energy than you would if you has regular swtiches and so on.