Hackers will often make rhymes or puns in order to convert an ordinary word or phrase into something more interesting. It is considered particularly flavorful if the phrase is bent so as to include some other jargon word; thus the computer hobbyist magazine "Dr. Dobb's Journal" is almost always referred to among hackers as `Dr. Frob's Journal' or simply `Dr. Frob's'. Terms of this kind that have been in fairly wide use include names for newspapers:
Boston Herald => Horrid (or Harried) Boston Globe => Boston Glob Houston (or San Francisco) Chronicle => the Crocknicle (or the Comical) New York Times => New York Slime Wall Street Journal => Wall Street Urinal
However, terms like these are often made up on the spur of the moment. Standard examples include:
Data General => Dirty Genitals IBM 360 => IBM Three-Sickly Government Property --- Do Not Duplicate (on keys) => Government Duplicity --- Do Not Propagate for historical reasons => for hysterical raisins Margaret Jacks Hall (the CS building at Stanford) => Marginal Hacks Hall Microsoft => Microsloth Internet Explorer => Internet Exploiter
This is not really similar to the Cockney rhyming slang it has been compared to in the past, because Cockney substitutions are opaque whereas hacker punning jargon is intentionally transparent.