Allan Kent, DMXzone Flash and PHP tutorial author, found Skipper at Sourceforge (the place to be if you're into OpenSource stuff, and not only for Linux - much of it has Windows versions too).
Skipper allows you to build very cheap sensors, has a program to translate body movements picked up by those sensors into controls for programs, provides word predictors, dictionaries etc, and interacts with screenreaders. And it's free!
Skipper is a free package for Linux that:
- Describes simple sensors that can be built at home, or re-used from other applications, to enable people with severely limited or involuntary movements to signal to a PC - for about $15!
- Interprets each user's available movements uniquely to make the best use of them, and translates the signals into full keyboard and mouse control.
- Provides word predictors, specialist on-screen keyboard layouts for a variety of user abilities, specialist on-screen menus for application control, user definable phrase books, an interface to the free Festival voice synthesiser, and many other features to make full access to all the resources of the PC and Internet a practical reality.
- Reads to the user! People who have had impaired movement from birth often have limited reading skills, because they never had a chance to learn. So there's a program that uses Festival to read electronic books from Project Gutenberg to the user, and highlight each sentence as it reads it out. (That's the way most people learned to read - now everyone who needs one can have a retired office computer to read to them.)
The "manifesto" is also brilliant.