Eye mouse is a computationally efficient, reliable and cost effective solution for determination of gaze in real time. In a gaze determination system, images of the eye are taken by a camera and sent to an image processing system. The image is processed from a low resolution camera to determine the location of the user’s iris in relation to the rest of the eye. This location is passed through a specialized set of algorithms and gaze direction is determined. This data is used to control mouse events on a computer display.
You can download a beta version from here: http://eyemouse.org/