Source : Free On-Line Dictionary of Computing

Intrusion Countermeasure Electronics
     
         (ICE) A contrived acronym for security
        software, coined by {Usenet}ter Tom Maddox and popularised by
        {William Gibson}'s {cyberpunk} SF novels.  In Gibson's novels
        ICE software responds to intrusion by attempting to literally
        kill the intruder.
     
        The term is not in serious use as of 2000 apart from the
        commercial software product, {BlackICE} and a growing number
        of others.
     
        See also: {icebreaker}.
     
        [{Jargon File}]
     
        (2000-03-18)