Related terms: jack shit, diddly shit, jack diddly shit, jack diddly fucking shit, jack diddly squat shit.
Real citation: "and what's that gotta do with doing for the black community?
answer: "jack-diddly-iddly-shit, that's what." -- ned flanders"
(Jacob Bentley, Nov. 5, 1996, http://groups-beta.google.com/
Made-up citation: “With law school grades ranging from D+ to jack-diddly-iddly-shit, I may not have a future as the next Johnnie Cochran.”