Interesting PIC based project that can use your eyeball to move a mouse around –
EyeWhere is an electrooculargram (EOG) that will allow your eye position to dictate the position of a cursor on a computer screen.
At the moment, only the schematic, parts list, and PCB patterns are available. The price is $19.95. The total cost for the parts is approximately $75. The parts are not available here. If you wish to order the parts, you should check an electronic component vendor such as Digikey.
EyeWhere – Link.