It would be nice if some otherwise troublesome sites could be whitelisted on a per page basis. That would make it possible to use the spam blacklist against fake news sites, or borderline creditable news sites, while still being able to refer those sites in articles about them.
Only admins should be allowed to add a whitelist on a page or change it.
Example wikicode for a spam whitelist to be placed on a page for Cheap Tinfoil Hats inc.
<spam-whitelist> cheap-tinfoil-hats\.com </spam-whitelist>
It is possible to make a similar spam-blacklist tag, as it is observed that some articles can be spammed with specific links. Adding a page-specific blacklist can solve the problem without protecting the page or blocking the use of a site on all articles.
Ther should probably be similar tags for email-whitelist and email-blacklist.