how do you prevent computer related eye fatigue?
christefano: I play action video games:  Action video games improve eyesight:
  http://news.ycombinator.com/item?id=540072

Seriously, I make sure that I:  1. use large displays so that I'm not squinting
  2. have decent fonts to write with (Panic Sans is my current favorite for code)
  3. blink a lot
  4. have a lot of lutein in my diet: http://en.wikipedia.org/wiki/Lutein