It doesn't have to be a virus going through your address book. Spammers now hijack addresses which are in the public domain, copy them to the "from" field and use them to desseminate their garbage. Several of us at RDNA have been attacked this way, and I've received stuff supposedly from other 3D sites. It seems this particular spam set-up has targeted the 3D community. Don't ever open anything you're not expecting!!