[Agrajag]

Just a piece of advice, Merlin, in case you haven't already done so, get a really comfortable chair, even if it is expensive.
I used to sit on one of those generic swivel chairs and sometimes had pains in the neck or back after many hours of gaming. Now I'm sitting in an uber-comfortable chair (with all sorts of swiveling, leaning back, adjustable handles etc.) and am feeling awesome even after many hours of sitting down.