Note: I'm putting this in the tools section because it can help with Diablo, or computers in general. It may belong in the off-topic board, though.
I found this neat little program "F.lux" yesterday and have been using it since. For the past few days, I've worked on www.freelancer.com, giving me plenty of exposure to my laptop's screen. As a lot of you have found, extended sessions at a computer (or TV) can cause strain on the eyes and headaches.
F.lux is a small program that looks at your time zone and tints your screen an orange/peach color in an attempt to reduce and remove the effects on your eyes. The colors are a lot softer, and though the orange can be strange at first, a few hours will get you used to it.
By default, the program tints your screen as the sun sets in your time zone, to create the softer light that your eyes are used to from evolution/creation/whatever. At night, your computer screen has a lot more light than you should get and F.lux dampens that a lot.
So far the program is working great (I have it set to all tinted, all the time) and I'm only feeling is a little tired (probably because the soft light I've had all day...may need to change the options).
Actually this is interesting, I just installed it (its nightime here so it was automatically set on the lowest tint) and used it for 20 mins, then I removed the tint to turn the screen back to normal and I was practically blinded XD. Even though I was using an un-tinted screen for the last 5 hours and didnt feel like it was too bright, the difference is astonishing.