Also clear head lights; the difference between clear and foggy lenses is amazing.
Cloudy vs clear and yellowed vs clear for reference; the sides with clear lenses look a few years newer.
I just did mine and wish I would have done a before and after. This is the only product you need. You apply it like wax and buff it off. Mine look brand new.
http://www.amazon.com/BlueMagic-725-Headlight-Lens-Restorer/dp/B001PH0WUU