I received one from another member that looked suspicious so I PM'd him to verify it and he confirmed that something had gotten into his address book and was sending the Viagra/drug email out.
Yep, that's exactly what happened to me. It wasn't a virus but it was a e-mail password exploit. I changed my password as soon as I realized what was going on and that solved the problem. I had responded to an e-mail from an old friend that had stated that she had changed her e-mail address. There were no attachments so I thought nothing of it, and since I use Windows Live Mail, there was nothing technically on my machine so my anti-virus didn't catch it. sigh.... You'd think people had better things to do with their time than come up with a Windows Live exploit. I've been avoiding getting Outlook 2007 but I guess it's time to just shell out the cash and quit being such a software cheapskate.
