Many of my graphic designer and computer geek friends have some form of carpal tunnel syndrome. Several have had operations, and some are nearly crippled. Women seem to be the most frequent sufferers, but I know a few men with hand problems also.
I first began having hand problems about 6 or 7 years ago, and realized I would have to get serious about changing the way I used my hands to prevent them from getting worse. The first thing that had to go was the mouse. I bought a Wacom tablet which eliminated most of the click and hold activity - you still click and hold but you do it by simply dropping the pen to the tablet and moving it across from the drop point.
The other problematic movement for me was scrolling. To cut down on the amount of scrolling I do with my right hand, I added a Kensington Orbit trackball on the left side. So I do fine detail work and precise positioning with my right hand, and big scrolling movements with the left.
On days when my hands have just plain had enough, I take breaks and relax my hands with a trick learned from a manicurist: massage the forearms by grasping my forearm near the elbow, between the thumb and forefinger of the other hand. Then draw the fingers up the arm toward the hand putting some pressure on the arm as they move up. If necessary I quit doing the offending task, for the rest of the day, period.