I was considering setting up a brain-computer interface for typing. There are a lot of existing BCI hardware systems out there, and you could hook them into Dasher), a program for the disabled that makes it easy to point a mouse or finger at the keys they want to type, and makes likelier keys easier to hit.
Idea free for the stealing.
Still, keyboards are pretty effective (I use Pentadactyl to browse the web using just the keyboard), so I would think you could find a better keyboard somehow that could work for you.
If someone is looking for something like Pentadactyl but for Chrome, I recommend Vimium. It adds tons of keyboard shortcuts that make keyboard-based browsing awesome.
I'm thinking about writing a more substantive post about how humans work and how we can work better, a little like this one. As is common with these sorts of things, once I started to do research and pull on various threads, it turned out that the field was pretty deep and would require time to understand. But in the meantime, I just thought I would link to this video of someone programming using only their voice.
As I suffer with symptoms of carpal tunnel syndrome, this is of particular interest to me. Once I watched it I decided to start looking at different voice recognition software so that I could still get some work done while typing less. I'm happy to say that even the default software for speech recognition which came with windows is actually very able and accurate. I dictated almost this entire post using that software.
As far as I can tell, Dragon Naturally Speaking is the gold standard in voice recognition software. It does come with a pretty hefty price tag, but it may be worth it if you have serious repetitive stress injuries, or as a preventative measure if you're someone who spends a lot of time at their computer. And if that doesn't work, chances are good your computer has adequate software pre-installed.