Strange feeling watching the first computer mouse demo, first TODO list tutorial, code folding, auto numbering etc. According to Wikipedia he never received any royalties for his mouse invention.
That's accurate. In recognition of his contributions Logitech Inc (the American branch) offered him and his institute space on their grounds.
Emacs supports them for example. You can buy hardware chorded keyboards like the Bat.
I think the problem is they come with a large learning curve for prose--just imagine learning to touch type again--but then multiply that by a few factors to do programming with all the symbols to be efficient. Ye olde 101 key keyboard is about the fastest thing there is right now, balancing keyboard size and key-to-semantic entropy.
I think it's coming back with smart watches. They can sense the ligaments in your wrist and know what letters you're "air typing"