I suspect that few of my readers have AOL. My mother is on AOL, and yesterday, AOL was unable to connect, and similarly with Facebook. Yes, I am aware of the DNSChanger problem--but she can browse with Internet Explorer, and we were able to get Skype working on her PC yesterday. Does AOL's email program use DNS settings that are different from the rest of Windows? That seems unlikely. (I'm not even sure if it is possible.)
UPDATE: I deleted the existing connections information (which probably included DNS settings, although AOL does its best to hide the technical details), and the problem went away.