You've got a bunch of responses already, but I thought I'd just point out, mostly for the benefit of those who might be in the danger zone, what CTS is, and how you get it.
When you curl your fingers to make a fist, you're using muscles in the hand to do so. When you straighten them, however, you're using muscles in the arm, between the elbow and the wrist. Tendons run from these muscles down to your fingers, to pull them straight. These tendons run through a narrow passage inside the wrist, and all the nerves carrying signals to and from the hand run through the same passage. This passage is the carpal tunnel.
Repetitive motion will pull those tendons back and forth, back and forth through the tunnel, and if you're unlucky, this will cause them to become inflamed and swollen. They then squeeze the nerves in the tunnel with them, and you've got pain and numbness -- CTS.
When you have to do repetitive flexing of the fingers, as in typing, piano playing, or, in fact, various types of mechanical work, the key is to keep your wrist straight. This lets the tendons run as smoothly as possible through the carpal tunnel. If you've got your wrist bent at an angle, the tendons will be sliding around that bend, and will rub all the harder on the inside wall of the tunnel.
CTS surgery involves opening up the carpal tunnel to make more room for movement through it.
-tih