I've heard plenty of stories about people getting serious medical problems from extensive use of keyboards and mice(among other things). I know we've discussed fancy ergonomic keyboards and related stuff a couple of times before, and while I'm sure some are very good, they're far too expensive for me(and i'd guess also for most other people who'd consider them), and I don't type all that much anyway.

So, for avoiding these problems, here's my latest whacky idea: offloading some controlls to feet/toes. Specifically:
-using something with large keys/buttons for some commonly used functions. One of those separate numeric keypads could be useful for that, but I can't seem to find one with more than one double sized key. So I'm leaning towards getting a second keyboard(preferably miniature but with full sized keys), and ripping out some keys to make others more accessible. I don't know if two keyboards can be plugged in at once with no issues.
-using a trackball with a foot for scrolling. The main issue obviously is whether it would be possible to reprogram the axes of one mouse to scroll, while having a second mouse and not affecting it.

I've heard some claims that trackballs are less strenuous on your hands than mice, so with the trackball idea trying it out normally first would be an added bonus.

RSI.

Here's some quick Google links:

http://eeshop.unl.edu/rsi.html#WHAT

http://www.pcstats.com/articleview.cfm?articleID=835

Three easy tips
* Learn to use your left hand for your mouse sometimes (eg. browsing), to give your right hand a rest.
* Improve your whole body posture at your keyboard, to have a better hand and wrist angle
* Check your wrist position when you are sleeping, you can have a bad wrist position which gives you carpal tunnel syndrome when your body should be resting.

I don't think that going to work very well with a mouse designed for a right hand, or if there's not much room to the left of the keyboard. So, again, the question is whether two mice, ie. a mouse and a trackball, can be used at the same time. In suse linux, in the mouse configuration menu, there is a "mouse 1" tab, so that implies that you can use multiple mice(at least in linux).

I've just rememebered, the only situation in which my hand(s) really hurt is when using a keyboard to play action type games(except pinball). I'd guess that not using a gamepad when it is the obvious choice is a very bad idea.

mathias....I'm already suffering a left hand problem, a arthritic condition in my left thumb (from an old injury). Fortunately I'm right-handed, and I do a bunch of things to protect that right hand.

With XP Pro, you can use two mice at the same time.....just plug in another mouse and it should work without any special settings. At my main computer I use a cordless mouse almost exclusively left-handed. And at my bedroom computer, I use a right-handed trackball mouse, which requires no wrist motion, and almost no hand motion.

I am also suffering some arthritis in my upper spine, which can make both hands go partially numb if I sleep in a bad position. To prevent that from happening, I arrange a bunch of big pillows so my spine/neck is relatively straight, and my arms are not crunched up. I have trained myself to change the sleeping position at least four times every night.

Needless-to-say, I avoid doing things that could further injure myself.....computer games are out. My exercise consists of work activities, and riding a stationary bike at home. It's Hell to grow older....but you can do things that will help out. Young people usually don't realize what is in store as their body ages.....

[rant]
bo ho, try being left handed. I use my right hand now and again when I cba moving the persons mouse to the other side of the pc, it really isn't that hard... [/rant]

It is appreciated that using a mouse with your left hand if you are right-handed is difficult, and vice-versa - that's why my post said "learn" to do that ...

I had a carpal tunnel problem in my right wrist a few months back, still had to work of course (self-employed), but cured it through doing "non-essential" PC tasks e.g. browsing using the left hand on the mouse, and generally resting the right hand as much as possible. Using the left hand of course feels weird at first but you get used to it after a few minutes, and it becomes instinctive within a few days. I would not yet be able to do accurate mousework all day with the left hand, but I think if you use it a little for browsing etc then if you ever were forced to use the left hand all day for work, it would be good to have already had some practice.

How is being left handed worse? If you're right handed, you use your right hand for the mouse, right letters, numpad, and arrow keys. If you're left handed, you're either using your left hand for the mouse and thus have the functions split more evenly, or if you're using your right hand for the mouse, then you're enly wearing out your worse hand.

Another idea: type / mouse with your feet. I'm sufficiently pododextrous to do so.

edit: OP posted that.... but I use feet in place of hands for _general_ keying/mousing.

Apparently, it's possible!