[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.