A useful thread a week or so ago revolved around ways to keep one's body reasonably fit while it's chained to a desk, grinding out reams of presumably deathless prose. Here's a writing-specific program for hands. Not just for avoiding carpal tunnel, but all the hand-wrist-forearm twinges.
You've probably seen these things. A little case holding a pair of matching balls (shut UP!). The most common styles are the cloisonne and the polished stainless steel. Usually they have a sounding plate inside, so that as they roll around you can imagine yourself being in a really tacky Cantonese chop suey joint ca. 1954.
I prefer the Chinese Health Balls, as they are known, that are carved from natural materials. I have a pair in white marble, several pairs in some kind of parti-colored marble, and a large set in honey-colored jade that I picked up in a little store in Chinatown for a buck!
http://en.wikipedia.org/wiki/Baoding_Balls
The technique is simple. You hold the balls in the palm of your hand and move your fingers so that the balls move around in a circle.
http://www.educatedhands.com/home.htm
As you get better you can work on keeping the balls apart or using more than two
http://wewin.com/The-Art-of-Chinese-Baoding-Balls.aspx.
Once you've gotten to the point where you can spin them around in a consistent manner for a couple of minutes, you'll notice that your hands seem bigger and are much looser. A couple of minutes a day will suffice, but clearly you can extend that time. Do it while you're watching the news.
Also, those of you who find that you get your best ideas while doing some kind of rhythmic activity (shut UP!) will see that using the baoding balls will work in that fashion, once you've gotten it to the point where you don't need to think about it.
Those with an interest in Chinese medicine will recognize that the balls are putting pressure on a very important point in the meridians. It's felt that they're opening critical chi gates. Be as skeptical as you like. I used to scoff at acupuncture until I had it.
PS: I can't resist attaching a file that relates to this subject visually.
HOWEVER:
it's absolutely not PC on several grounds, so please don't complain. It's vulgar, and it makes fun of a certain vowel-heavy nationality (but some of them actually made and acted in it). I think it's funny as hell.