/I-C-E/
[coined by USENETter Tom Maddox, popularized by William Gibson's cyberpunk SF novels: acronym for Intrusion Countermeasure Electronics]
Security software (in Gibson's novels, software that responds to intrusion by attempting to literally kill the intruder). Also, icebreaker: a program designed for cracking security on a system. Neither term is in serious use yet as of mid-1991, but many hackers find the metaphor attractive, and each may develop a denotation in the future.