Confirm account means that a new user will not be able to quickly correct typos etc. Isn't there a simple way to add a captcha to mediawiki.
Just found one (I had missed it when I sent my previous e-mail): http://www.mediawiki.org/wiki/Extension:ReCAPTCHA, nowadays merged into http://www.mediawiki.org/wiki/Extension:ConfirmEdit (which is not ConfirmAccount). ConfirmEdit can be configured to only present captchas to non-logged-in users, when they try to edit or create a page, or create an account. Might that be useful? Or we could go old-school copy protection style: "What is the fifth word on page 120 of the TeXbook?" :-P If we want to have a slightly higher barrier of entry: "Name one undocumented command that you recently heard about on the mailing list." ;-) Cheers, Sietse