Embrace the compact flourescent lamps (CFL's) and ditch the incandescent bulbs. These swirly little glowers give more light with less energy. A CFL of 26 watts equates to your standard 100 watt bulb.
These CFL's use only one quarter of the electricity and last several years longer than incandescent bulbs. But because they contain 5 mg of mercury, you can't throw them out with the rest of the garbage. Instead you should recycle them properly. Even though this is a small scale way to reduce your carbon footprint, if half the country made the switch, we could offset 20,600,000 TONS of carbon emissions per year. That equals 41,250,000,000 pounds of pollutants!