I was having a little brainstorming on this subject - and thought that it might be possible to enable 'website' field on Profile Editing ONLY, and ONLY to those users who has left not less than $allowHyperlinks of messages on forum.
What do you think?
I could even include this in the official package of miniBB, at least to try... I think, this approach should make further automated registrations nonsensical, as it will be impossible to fill in the website field when creating a new account; and IF such field still will be filled in, we can use the (above) approach to simply deny registration, if this field has a value.
Also, the value of this field should be eliminated as soon as the script sees this member has less than $allowHyperlinks of messages. This is for "hard-to-take" spammers - let's say, user registers a valid account without Website field value; on the next step, he creates couple of stupid not meaningful messages to rich the limit criteria and fills in the Website field (the script will allow that). Further, the Admin comes to forum and deletes messages, so this member, again, has 0 posts - at this process, the script should zero Website field as well. So it could be quite easy to handle - I just need to extend the messages/topics deletion function.
Well, it may look complicated, but at least this starts to look like an approach, not just a suggestion... WDYT?