[muxxa]

Nobody here has mentioned stress.

I suffered from a lot of wrist pain (RSI) for a number of years, tried everything including alternative keyboards and trackball mice. The only physical 'device' that improved things was getting a proper chair with actual armrests (which I assumed would make things worse by constricting arm movement).

When I read an article mentioning a book called 'The Mind Body Problem' (I didn't actually read the book), the penny dropped.

My mental state of agitation, of needing to 'get shit done' was translating into increased tension in my wrists. Just recognizing this has pretty much solved my RSI problems (going strong for over a year). This explains why some people can work on laptops etc. in the most contorted positions without ever having any adverse physical effects - they are not under any mental stress.

[1] http://www.bookdepository.co.uk/Mind-Body-Problem-Rebecca-Go...