I help support a local organization's computers. I think the secretary's computer's winsock is infected, but i'm afraid to fix it just now, because it might mess it up. So, i disabled IE with a bogus proxy server, and expected them to use Firefox.
I just got an email from someone saying he can't connect to the Internet from that computer. After finding out what happened, i explained to him that i "turned off Internet Explorer" on that computer. I should be ashamed of myself. But, it got the message across quickly and clearly.