My parents visited Israel when I was a kid. My grandparents' apartment had Israeli air-raid-quality shutters which ACTUALLY blocked out all the light; they were wooden slats that rolled down and stacked themselves solidly over the outside of the window. You pulled on the cord and the light went out completely - that simple. I expect it helped on noise reduction too, though I wasn't checking then. Ever since, I've taken the lack of this simple, extremely useful feature on any other windows I've ever seen, as proof that the housing industry is dysfunctional.