Stanford University scientists have created a way to use browse the web without the use of a mouse:
A researcher at Stanford has created an alternative to the mouse that allows a person using a computer to click links, highlight text, and scroll simply by looking at the screen and tapping a key on the keyboard. By using standard eye-tracking hardware--a specialized computer screen with a high-definition camera and infrared lights--Manu Kumar, a doctoral student who works with computer-science professor Terry Winograd, has developed a novel user interface that is easy to operate.
Link - via The Presurfer
Besides, apart from what i think it's a great idea in general, if this kind of interface becomes more and more accessible to the general population, special applications for all the users that suffer some kind of disability tend to a) get perfected, and b) become more reasonably accessible worldwide.