I'd lock myself out of my own site. I was trying to set the login box not be visible to users, but now I have no clue how am I going to sign on.
If you've disabled the "User-Login" -block and need to login, just visit the login page directly:
http://yourdomain.com/?q=user(if clean URLs are not enabled)- OR
http://yourdomain.com/user(if clean URLs are enabled)
Note: Don't use any user-ID in the link, just the word "user"