The amount of coding I do, not to mention guitar playing, working out, etc. my wrists/forearms undergo tremendous strain. I've mitigated a great deal of this for roughly the past year by using a product called DataHands (datahands.com) for data input.
They help a LOT. They eliminate 80% of finger movement, and when you really get them, they are faster then regular keyboards.
However, they don't work in SL. I've tested them in a number of other games, they seem to work fine; I use them every day without problems of any kind.
The specific issue is, the mouse controls/arrow keys don't work. They "stutter", as if I'm ultra-quickly tapping the arrow key instead of holding it down. Being as motion in SL is largely keyboard driven, that makes using DataHands to get around pretty much impossible (keep in mind one of the reasons to use DataHands is to cut down on mouse usage, which is also bad for your forearms and tendons on the back of your hands...so mapping movement to the mouse isn't a good answer).
In general, DataHands get recognized as a standard mouse/keyboard; I've never had to install any special kind of driver, Windows just picks them up as keyboard and mouse (they have 2 seperate inputs, one for mouse, one for keyboard).
What would be the best way to troubleshoot the issue? SL doesn't crash, there are no events in the logs, I never actually see an error of any kind...they just don't work, and I sort of need them to, as using keyboards for hours of coding to play a game is just out of the question.