I also have a lamp aimed at the keyboard and a floor lamp above my desk, but those are the only lights I leave on in here at night when I'm online for the most part, unless I'm working on something offline as well then both floor lamps are on.

But I just tend to have trouble with the darker backgrounds, so I steer away from them and go with a dark color or black on a pastel background, but not always white.

Edit: I forgot, I also used to be fine with those odd dark green backgrounds commonly used in cathode ray tubes. Those never bothered me.

And yeah, my eyes have had problems for years, I've worn glasses since gradeschool, and I don't do contacts.

Brenda