I'm not inclined to impose extra requirements on Math-Fun subscribers without a very good reason. My opinion is that requiring virus-protection software won't do much to prevent the problem of subscriber email addresses showing up as bogus senders of viruses. The people who run Windows already have their hands full with security troubles, and are doing what they can to cope. Many of them have no effective control over their configuration, being stuck with whatever work or school provides. Xmission provides fairly good spam & virus control: As moderator, I have to discard a modest number of junk messages, but it's minor. So you probably won't get spam/viruses directly from the list. (No promises.) But the problem David Wilson describes, a presumed triangle of victims of various kinds, poses a big problem for Whitelisting, an otherwise very effective defense method. Many of us are already in a lot of address books, and thinning out the math-fun subscribers won't make much difference. I've had this problem in an odd kind of ghosting mode: Spam from one of my email accounts to another. It took a while for me to figure out that the From address was simply a forgery. I'll let people discuss this *if they must* for 3 days. If you just can't stop yourself from posting, please try to say something new, that we haven't heard before. Remember that very few people signed up for this list to discuss mailing list security problems. I'll be away for 10 days starting Saturday, so you're on your honor to behave. If the security discussion gets out of hand, you can try using the web interface to unsubscribe or temporarily turn things off, or switch to digest mode. Rich rcs@cs.arizona.edu