For those who need a rest from keyboard stress, or for mobile / wearable use:

This feather light, Feather-Touch USB device allows full keyboard emulation. with one light stroke of the finger or thumb for each character. Faster than Graffiti, it is silent and can even be used without looking. Available now at our Yahoo Store. Introductory price $159.95. Reviewed by The-Gadgeteer.com. Requires Windows XP or 2000. Win 98 now available, too)