Some of the Weirder Ideas From CHI 2009
An anonymous reader writes "Technology Review has a roundup of some of the weirder ideas on show at last week's Computer-Human Interaction conference in Boston. They include a trackball that heats up as you roll over different parts of an image, a pair of goggles that track eye movements using electrooculography, and a miniature robot with a cellphone for its head."
You might want to look at opengazer
http://www.inference.phy.cam.ac.uk/opengazer/
For a while development had been abandoned but that disclaimer has now disappeared from the website so I imagine someone is working on it.
The same people created the dasher text input system which is really worth having a look at as an example of innovative input methods.
http://www.inference.phy.cam.ac.uk/dasher/
Your eye already has markings with can be tracked.