We have gradually replaced every light bulb in our home with the more energy efficient ones. We just replaced as the old ones burned out. They produce no heat, last about 10 times longer and are very energy efficient. They are expensive to buy all at once, so we just bought a couple at a time and replaced as they died.
In the sunroom/sewing room, we have pot lights in the ceiling, plus a ceiling fan. They even make the bulbs (like spotlights) in the more energy efficient ones. Helps reduce the heat tremendously since that room is on the west side of our house.