Whew! after receiving an email that the forum was 'taken over' by viagra ads, i logged on (ok, for the first time in a while) to discover it was true. i've added a module called spambot that will help with this. for an admin looking at a user account there is a tab called 'spam' which will allow you to unpublish all posts. i also changed our registration setting so that anyone who wants to be an needs to be an authenticated user needs admin approval. to post anything at all one needs to be authenticated. most of our users are verified, the next level up from authenticated. i also blocked users who have posted obviously spammy content (and added spammer_ to their username), and unpublished this content (you can see them in the Content listing, with a 'not published' note). for the hundreds of posts by frederic37b, i deleted them all, and blocked the user. There are a flock of recently-joined authenticated users, who joined before users needed admin approval. i think we will see whether they try to spam or not in the next month or so. If they do, it will be obvious.
We might should consider how to let people know how to join us. Then again, like the person who emailed me, those who want to get involved will find a way.
Everything i did today is subject to y'alls agreement. i took action because the spam was overwhelming our user content. there may be better solutions than what i did. i'm as usual open to ideas, feedback and loving criticism :)