The Jargon File (version 4.4.7, 29 Dec 2003):

psyton
 /si:'ton/, n.

    [TMRC] The elementary particle carrying the sinister force. The probability
    of a process losing is proportional to the number of psytons falling on it.
    Psytons are generated by observers, which is why demos are more likely to
    fail when lots of people are watching. [This term appears to have been
    largely superseded by bogon; see also quantum bogodynamics. ?ESR]


The Free On-line Dictionary of Computing (30 December 2018):

psyton

    /si:'ton/ (From TMRC) The elementary particle
   carrying the sinister force.  The probability of a process
   losing is proportional to the number of psytons falling on it.
   Psytons are generated by observers, which is why demos are
   more likely to fail when lots of people are watching.  This
   term appears to have been largely superseded by bogon; see
   also quantum bogodynamics.

   (1997-04-26)