Always sit at least 6 feet from the television and play video games in a well lit room.
*http://www.youtube.com/watch?v=BlDDjlME_54*
I do the 20/20/20 procedure:
Every 20 minuets, look at something 20 feet away for 20 seconds.
I saw it on the news last year or the year before.
I work in an Optometry doing IT work, and I don't do this (I know, I should...) I do, however, have an unlimited supply of eye drops.