Halogen Incandescents will save you about 25% in energy savings.
Not the best choice among your lighting energy saving choices, but better than your traditional lightbulb. Halogen Incandescents are simply an energy efficient incandescent. They have a capsule which holds the halogen gas which increases the lifespan and increases the energy efficiency of the bulb. They will last about 3 times longer than your traditional bulb.