Hello!
SmiteSpam (https://www.mediawiki.org/wiki/Extension:SmiteSpam) is a new extension that helps wiki admins identify and delete spam pages (and block their creators).
For wikis that are overrun with spam, this extension could reduce the enormous amount of time required (to manually find and delete spam pages and then block their creators) from the hours or days it normally takes, to just minutes!
The page on mediawiki.org linked above has setup and configuration details. Feedback on the talk page is very welcome. The Phabricator project for this extension is at https://phabricator.wikimedia.org/tag/mediawiki-extensions-smitespam/.
The extension was developed by me as a GSoC project this summer, mentored by Yaron Koren and Jan Luca.
-- Vivek Ghaisas (polybuildr)