I have a few internal .net web application here that require users to \"log out\" of them. I know this may seem moot on an Intranet application, but nonetheless it is there.
Well, I've been browsing around Bugzilla for a bit now and seemingly the best way you can go for clearing the authentication would be to send non-existant credentials.
Read more here: https://bugzilla.mozilla.org/show_bug.cgi?id=287957