At my office I swap out my keyboard about once or twice a year. There is always a surplus of new keyboards in the box, just sitting in the IT closet. I am hard on my keyboards (type like a freaking Sasquatch) and so they break under my daily abuse.
I use a product called "Office Duster" once per week and wipe the keys down with Q-tips soaked in alcohol once per month. I'm obsessive compulsive so I wash my hands eight to ten times per day day (minimum) while at the office. No germs here!
