Pedigree, what do you think of the following idea?
Many spammers use temporary / fake email providers. i.e.
harry1234@trashmail.net
Most fake / temporary email addresses disappear after 1 day or even 5 minutes.
Serious registration use real email providers. There are many temporary email providers and they keep changing their domain names to dodge or
I believe it would help against spam and trolls if there would be a database of temporary email domains. So that if a user registers with such an email domain, the registration is denied. Like with SFS: admins could submit the temporary domains. A system could be used that when an email domain is submitted by more than X vbulletin sites, the domain is marked as a temporary/fake email.
Admins who moderate their new registrations could submit such domains with the click of a button if the 'new users moderation' queue would have a button for it. Other admins could submit trough an adminCP/modcp option.