Abaddon wrote:

2 minutes in the microwave sterilizes sponges, scrub pads: study
Last Updated: Tuesday, January 23, 2007 | 4:11 PM ET
CBC News
Putting kitchen sponges and scrub pads in the microwave for two minutes can kill bacteria and viruses, eliminating the threat of food-borne illnesses, U.S. researchers say.
%22People often put their sponges and scrubbers in the dishwasher, but if they really want to decontaminate them and not just clean them, they should use the microwave,%22 lead researcher Gabriel Bitton, a University of Florida professor of environmental engineering, said in a release.

I found this kinda cool, I usually just throw out my old sponges...

Interesting... i occasionally soak my sponges in a bit of distilled white vinegar, which I believe is fairly effective against most bacteria, though I'm less sure about virii. I use vinegar to clean and disinfect my wood chopping block as well, though I suppose the facts that i don't use it for meat and don't allow it to stay moist are more relevant to it's safety.

Anyway, i suppose a microwaving might not be a bad idea from time to time...

RE: 2 minutes in the microwave sterilizes sponges, scrub pads: study