I draw your attention to the tag archive. Currently, there are 19 questions. There is no tag wiki or usage guidance.
There are a number of apps which have the concept of "archiving", not to mention the normal English definition of generically putting data/information away without deleting it. There are questions with this tag asking about: Gmail, Trello, SourceForge, Wikipedia, Twitter, Yammer, RSS, Postini, wired.com, digg.com, site "snapshots", WordPress, Google Voice, Google Reader, and the general Web.
This tag can't stand alone as the only tag on a question; it would always need another tag to give context. This seems to me to be a classic Meta tag.
As such, it should be removed from all questions to allow the system to auto-delete it.
(As always, if you participate in a clean up effort, be sure to fix all of the problems with a post, not just remove a singular tag.)