Spending thousand of hours in front of my computer, ergonomics became quickly a main issue.
For the monitor or the keyboard, technical solutions exist. But for the mouse, I never get used to the trackball and putting a little pillow under my wrist made me feel uncomfortable.
So I started to swap the hand that holds the mouse. It's great, one can rest while he other is working. At the beginning it was hard, but now I don't really see the difference unless I try to kick an ass at Quake III ;-)
Anyway, a lot of people would not be comfortable with this idea, do not have the time, and above all, can not afford the mental switch that comes with the use of the other hand. Indeed, using the other hand make you use the other side of you brain (logical <=> creative), making very hard to concentrate the first times.
I am happy about it but can understand that many people would not. Do you have a better idea ?