I feel that this is a much better place to ask this than a medical forum, we have ~250 people who spent most of their day in front of a computer.

Does anyone here have any experience with such injuries? How/when did you find out? What did you do (if anything)?

I don't know if I have the RSI, but I can tell you that I can "crack" my wrist and almost any one of my fingers whenever I want. Also, my wrist sometimes hurts me when I type for a very long time (especially on a laptop keyboard I have very long fingers so the palm is in an uncomfortable position most of the time) Is this normal?

I bought a Logitech Wave keyboard, obviously it feels much better than the laptop keyboard, but I can't really tell if it helps the "cracking" and my wrist still sometimes hurts.