laptop sunscreen (HA!)

I'm on my porch today because it's so nice out. But it's also sunny, so it's tough to see my laptop screen. I was fidgeting with it and found that it's actually easiest to see if the sun is over my shoulder shining straight on it. I then noticed that changing the brightness of my screen's back-light has no effect. It's all the way down (and so saving me considerable battery time) and I can still see pretty well. The colors are all washed out, but it's fine for stuff like writing and programming.