Vioguard has put out a self-sanitizing keyboard meant for hospital/medical settings. With the move to electronic charts and data input, there is increased concern about cross contamination/infection of medial personal.
This keyboard solves the problem by sterilizing itself with anti-bacterial ultraviolet light. When someone wants to use it, they wave their hand in front of the sensor and the keyboard pops out. The sensor just as you would come accord in public bathrooms. Once you are done, it automatically retracts to re-sanitize itself to get ready for the next person; or for your return. you can also force a retract by pressing a button; though that would seem to defeat the purpose as others may have clicked the button leaving traces of what you just avoided picking up by using this special keyboard.
At just under $900 they are not cheap, but not really expensive either for a hospital or other large institution that wants an easy solution to keeping a public computer keyboard sanitized.
Video embedded below. (from http://www.engadget.com/2009/10/12/vioguards-self-sanitizing-keyboard-means-maybe-we-dont-all-hav)