Source : Free On-Line Dictionary of Computing

FUBAR
     
        1. (WWII military slang) Fucked up beyond all
        recognition (or repair).
     
        See {foobar}.
     
        2.  The Failed UniBus Address Register in a
        {VAX}.  A good example of how jargon can occasionally be snuck
        past the {suits}.
     
        Larry Robinson  reports the following
        nonstandard use for FUBAR:
     
        One day somebody got mad at the {card reader} (or card eater
        that day) on our {Univac 3200}.  He taped a sign, "This thing
        is FUBAR", on the metal weight that sits on the stack of
        unread cards.  The sign stayed there for over a year.  One
        day, somebody said, "Don't forget to put the fubar on top of
        the stack".  It stuck!  We called that weight the fubar until
        they took away the machine.  The replacement card reader had
        two spring loaded card clamps, one for the feed and one for
        the return, and we called THOSE fubars until we dumped punch
        cards.
     
        Incidently, the way he taped the sign on the weight made up
        for the lack of a little nylon piece that was missing from it,
        and fixed the card reader.  That's why the sign stayed there.
     
        [{Jargon File}]
     
        (1997-03-18)