> We should switch all of the lists over to "subscribers only can post"
> and add in a special list so people with more than one address can
> subscribe to a "never gets mail but is allowed to post" list. Then the
> spam will all go away completely.

Go away completely?  Did you mean to say "the spam might decrease slightly" ?

Make spamming a capital offense.  Hunt down a few of them and hang them in
the public square.  Then you might see a decrease in spam.