I was watching This Old House and was surprised when they said that it might be more economical if you installed dimmer switches on your lighting fixtures. The fact of the matter is that if you convert you home to compact florescent lighting you will save the most money overall. Just in case you didn't know you can't dim a florescent fixture at all. Dimmers don't save any electricity at all they simply add resistance in the circuit that sends less power to the bulb but still consumes the same amount of power. All of the power that is not sent to the bulb is dissipated in the dimmer switch. Dimmer switches might make your incandescent last longer but that is only if you don't use the dimmer at 100%. Most people don't use a dimmer unless they want to set a mood, otherwise the dimmer is set to full. Compact florescent bulbs do two things use less energy and last 5 times longer.