I've been using a mouse since 1990. My first mouse driven computer was the Amiga A-500. Ever since then I have been using my right hand. Over the past year or so, I've been getting pain in my wrist (probably Carpal Tunnel but I'm too afraid to go to the doctor to find out). I have now switched to my left hand. Ever since 1990, I have spent many hours on the computer both at home and at work so it's understandable that this has happened. What is very interesting is that switching to my left hand was not all that difficult and Windows makes it easy by allowing users to switch the mouse buttons around in the control panel.