I've never yet failed to enjoy a TED lecture. I have to ration myself, because my satellite internet connection won't permit me to stream video for very many minutes in any one day. This lecture is about using off-the-shelf video game units to build for about $100 the kind of eyeball-controlled electronic devices that, up to now, paralyzed patients have had to pay $50,000 or even $200,000 for.
Patients with severe skeletal-muscular problems such as spinal injury or neurological disease tend to preserve their ability to control their eyes. Not only the optical nerve, but also the other eye-related nerves, are more like an extension of the brain itself, in contrast with your other bodily movements, which are mediated through the spine. When you add this ability to cunning little devices that track and respond to eye movements, it means that profoundly disabled people not only can web-surf but also can communicate and even drive mechanisms like wheelchairs. The lecturer in this video has figured out ways to make these devices so cheap that they're reasonably available to just about anyone.