Cleaning Your Mouse with your Fingernail, the "Handywoman's Secret Weapon"
Check out this tech tip... Unlike the previous tip about cleaning "e-dirt" from your computer, this one explains how to clean real dirt from your mouse with a fingernail. But not to worry all you fingernail-less folk, the tip of a small flathead screwdriver or a wooden manicure stick will also work.
I frequently have to do this with our public computers. It's amazing how much gunk builds up in there.
Source: Depraved Librarian