sign in and out

I don't see how to sign out, when I want to close my session here, at cucumis. I mean, ok, I signed in once , and then when I open the page again, I am already signed in.
How do I sign out?
Thks

"Log out" in the "Profile"

You are right, spring, it's not actually easy to find it, I think I will make it more clear (on all pages) in a future vesion of cucumis.