Functionality to build a list of parent (canonical) tags with their children (similar) tags. This will auto convert the similar tags to the canonical tag when one (or more) is used.
Page listing the canonical tags
Page to add/edit a canonical tag
Update (2016 May 28th):
@Xon has taken over this @Daniel Hood's add-on. This product is now available for purchase again. For more information read this thread.
Moderator Essentials provides your moderators with valuable tools and features that help make their daily tasks much easier...