Well, for one, I like what I do. And thus far I've been able to manage it by making some changes, over time. Basically all of these I learned about from other HN threads:

* first, switching between using L and R hands for mouse

* eventually, purchased a new mouse: Evoluent VerticalMouse 4 Right - neutralizes your wrist on mouse hand

* software that forces you to take breaks instead of just sitting and typing for hours straight. Workrave is what I use (http://www.workrave.org/) - freeware and lightweight. I take 12 second micro-breaks every 4.5 minutes and a 4 minute break ever 25. Get up, stretch around, wiggle your arms. Staring at a far away corner of the room helps w/ eye strain too

* for plane rides - small, wireless trackball has worked wonders. I can't use a laptop touchpad worth a damn