Another fun etymology (via wordorigins.org): pettifogger (“a lawyer who engages in petty quibbling and cavilling, or who employs dubious or underhanded legal practices”) is explained by the OED as simply petty plus the earlier fogger, and the OED says of the latter:
[Of somewhat obscure history; but prob. derived from Fugger, the surname of a renowned family of merchants and financiers of Augsburg in the 15th and 16th c.
The name passed as an appellative into several European langs. In German fugger, fucker, focker (see Grimm) has had the senses ‘monopolist, engrosser’, ‘usurer’, ‘man of great wealth’, ‘great merchant’, and, in certain dialects (doubtless originally through ironical use), ‘huckster, pedlar.’ Kilian 1598 has Flem. focker ‘monopolist, universal dealer’ (monopola, pantopola), giving fuggerus and fuccardus as popular mod.L. equivalents; and in mod.Du. rijke fokker is an avaricious rich man. Walloon foukeur and Sp. fúcar are contemptuous designations for a man of great wealth. A ‘petty Fugger’ would mean one who on a small scale practises the dishonourable devices for gain poularly attributed to great financiers; it seems possible that the phrase ‘petty fogger of the law’, applied in this sense to some notorious person, may have caught the popular fancy, and so have given rise to the specialized use in sense 1. ...]
1. A person given to underhand practices for the sake of gain; chiefly, a contemptuous designation for a lawyer of a low class. Usually preceded by petty (see PETTIFOGGER). Obs.
1576 FLEMING Panopl. Epist. 320 As for this pettie fogger, this false fellowe that is in no credite or countenance. [...]
Yes, the jokes write themselves.