I've worked taking care of animals, and I've also worked taking care of computer users. I'd have to say that the tolerance that computer users have for using thoroughly disgusting keyboards, mice and mousepads has driven me to further extremes of personal hygiene than any work I've done with animals. YUCK!
I second (or third, fourth, ...) the use of some alcohol-based hand disinfectant and a regular washing of your hands to keep most of the surface funk under control, but I also clean my keyboards once a year (disassemble, clean using alcohol-based cleaner/disinfectant, ressemble), just to get all of the other extraneous matter that may drop in behind the keys (including dust, hair, dander, etc.)
I also use an iSkin or equivalent on laptop keyboards.