This tip about setting the brightness contrast really helped- i usually use high contrast, and low bright.. and that makes the screen really flare up.

Another thing I try to do is: us a lamp! I place it lighting up something on my peripherals, that helps.

Also, I had a black monitor for a while.. and it hurt my eyes.. switched it for a light grey one and it was a lot better. it seems when your vision is too preocuppied by the monitor, it freaks the eyes out?

( i take smoke/coffee breaks every half hour : ) )