How many eco-aware Moms does it take to change a light bulb? Just one: You. When your old incandescent bulbs burn out, replace them with longer-lasting, low-energy compact fluorescent bulbs (CFLs). Available at any hardware or home store, CFLs cost a bit more than traditional bulbs, but because they use only a fraction of the electricity, you'll lower your electric bill and pay less in the long run. (CFLs, by the way, last up to 10 times longer than incandescents.) When shopping for CLFs, pick up a bulb about one-quarter the wattage you're looking to replace; for a traditional 75-watt bulb, for example, use an Energy Star CFL in the 18-watt range. To save even more on lighting -- both indoors and out -- use timers and install dimmer switches. Do read the directions, though, when selecting your new CFL bulbs: For a CFL to work in a dimmer, it must be specifically designed to do so.