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

crufty
 /kruhf'tee/, adj.

    [very common; origin unknown; poss. from ?crusty? or ?cruddy?]

    1. Poorly built, possibly over-complex. The canonical example is ?This is
    standard old crufty DEC software?. In fact, one fanciful theory of the
    origin of crufty holds that was originally a mutation of ?crusty? applied
    to DEC software so old that the ?s? characters were tall and skinny,
    looking more like ?f? characters.

    2. Unpleasant, especially to the touch, often with encrusted junk. Like
    spilled coffee smeared with peanut butter and catsup.

    3. Generally unpleasant.

    4. (sometimes spelled cruftie) n. A small crufty object (see frob); often
    one that doesn't fit well into the scheme of things. ?A LISP property list
    is a good place to store crufties (or, collectively, random cruft).?

    This term is one of the oldest in the jargon and no one is sure of its
    etymology, but it is suggestive that there is a Cruft Hall at Harvard
    University which is part of the old physics building; it's said to have
    been the physics department's radar lab during WWII. To this day (early
    1993) the windows appear to be full of random techno-junk. MIT or Lincoln
    Labs people may well have coined the term as a knock on the competition.