Source : Free On-Line Dictionary of Computing

brain fart
     
         1. The actual result of a {braino}, as
        opposed to the mental {glitch} that is the braino itself.
        E.g. typing "dir" on a {Unix box} after a session with
        {MS-DOS}.
     
        2. A biproduct of a bloated mind producing information
        effortlessly.  A burst of useful information. "I know you're
        busy on the Microsoft story, but can you give us a brain fart
        on the Mitnik bust?"
     
        (1997-04-29)