Turn down the temperature of your water heater to the warm setting (120°F). You'll not only save energy, you'll avoid scalding your hands

Start using energy-saving settings on refrigerators, dishwashers, washing machines, and clothes dryers.

Survey your incandescent lights for opportunities to replace them with compact fluorescents (CFLs). These lamps can save three-quarters of the electricity used by incandescents. The best targets are 60-100W bulbs used several hours a day. New CFLs come in many sizes and styles to fit in most standard fixtures.

Check the age and condition of your major appliances, especially the refrigerator. You may want to replace it with a more energy-efficient model before it dies.

Clean or replace furnace, air-conditioner, and heat-pump filters.

If you have one of those silent guzzlers, a waterbed, make your bed today. The covers will insulate it, and save up to one-third of the energy it uses.

More tips here.