I've noticed that when I log out from the site, and even from Stack Exchange (I'm using StackExchange OpenID), I'm not fully logged out.
When I click 'log in', I'm automatically logged in using my account. This is not acceptable because anyone using the same browser on the same computer will gain access to my account.
So my question is, how to fully log out from Stack Exchange? Is it required to delete cookies? Are those only the cookies for stackexchange.com and its subdomains? Or is some persistent cookie mechanism (like EverCookie) used?