This is a shadowy and secret page that only people are are "Known" to the wiki can edit though that everyone can view.
It's basically a test of moinmoin's new ACL support.
See HelpOnAccessControlLists for more information.
I've also created an ["ACLTestUnreadablePage"] that only known users can read to see what that looks like.
Note, I'm not intending to destroy WhyWikiWorks by using this though it might mean I keep private todo lists on here more now.