-- Breaks should be taken every 30-45 minutes for at least 5 minutes. If you need assistance there are free downloadable timers that will help remind you to do so.
-- Stretch your arms, hands, neck, and back during breaks. This yoga site demonstrates some exercises. Other sites are listed below.
-- Maintain posture alignment. Don't slouch on the couch with the laptop.
-- Work stations should be reviewed initially and with each office move. Adjust your chair, monitor, keyboard, mouse, laptop. Alternate keyboards and mice periodically.
--Shift your gaze from the computer screen to the distance. And don't forget to blink!
--Limit non-essential computer use. This may be heresy -- but do give the surfing, gaming, emailing, and text messaging a rest.
-- If pain occurs or persists, see your doctor, who may recommend wrist brace, ice packs, anti-inflammatory medication such as ibuprofen, cortisone injections, physical therapy, and most importantly, rest to allow healing. Don't procrastinate in addressing your symptoms -- the sooner you tend to them, the better off you are.

And finally, here are more sites that may be helpful:
Safe Computing Tips
Alternative Pointing Devices
Alternative and Ergonomic Keyboards
Harvard RSI Action
RSI exercises
RSI Page

Update: One more: Boston U.'s Ergonomics Self-Help Guide (Flash)

-- Breaks should be taken every 30-45 minutes for at least 5 minutes. If you need assistance there are free downloadable timers that will help remind you to do so.
-- Stretch your arms, hands, neck, and back during breaks. This yoga site demonstrates some exercises. Other sites are listed below.
-- Maintain posture alignment. Don't slouch on the couch with the laptop.
-- Work stations should be reviewed initially and with each office move. Adjust your chair, monitor, keyboard, mouse, laptop. Alternate keyboards and mice periodically.
--Shift your gaze from the computer screen to the distance. And don't forget to blink!
--Limit non-essential computer use. This may be heresy -- but do give the surfing, gaming, emailing, and text messaging a rest.
-- If pain occurs or persists, see your doctor, who may recommend wrist brace, ice packs, anti-inflammatory medication such as ibuprofen, cortisone injections, physical therapy, and most importantly, rest to allow healing. Don't procrastinate in addressing your symptoms -- the sooner you tend to them, the better off you are.

And finally, here are more sites that may be helpful:
Safe Computing Tips
Alternative Pointing Devices
Alternative and Ergonomic Keyboards
Harvard RSI Action
RSI exercises
RSI Page

Update: One more: Boston U.'s Ergonomics Self-Help Guide (Flash)