It's hard enough for me to compute on a chair, with a keyboard. I got a glimpse of myself on a bed looking up at a monitor and thought, "Hell no, I would not like a monitor above my head during an earthquake." Enter the video bouncer:
Simple programming and/or minor engineering required for this. Make the image of the computer screen reverse and upside down, then bounce the image to a safety mirror (thin film of mirror material over lighter backing) above your bed. Voila, you can compute on your back, looking up at the screen projected above. I guess an even better solution would be to literally project the image onto the same location, again in reverse, but projectors aint cheap.
Okay, just as good would be the video glasses thingamajig, still expensive. Further, a foundation should be started to help people with disabilities use computers. Does Hawking have a foundation of this sort? Everyone needs computer and net access, for sure. It should be an inalienable right, frankly. Go $100 Laptoppers!