Turn off the lights in any room you are not using and consider installing timers, photo cells, or occupancy sensors to reduce the amount of time your lights are on.
Use task lighting; instead of brightly lighting an entire room, focus the light where you need it. For example, use fluorescent under-cabinet lighting for kitchen sinks and countertops under cabinets.
Consider three-way lamps. They make it easier to keep lighting levels low when bright light is not necessary.
Use 4-foot fluorescent fixtures with reflective backing and electronic ballasts for your workroom, garage, and laundry areas.
Consider using 4-watt mini-fluorescent or electro-luminescent night lights. Both lights are much more efficient than their incandescent counterparts, and the luminescent lights are cool to the touch.