Gervase - ah well, as I understood it, the finger in balled fist - the Figoe - represents a fruit stone projecting from the anus, which the person you wish to insult is invited to extract with his mouth, How rude. Can anyone throw any light on the origins of this delightful folk custom? There is an Italian gesture of putting ones thumbnail under ones front incisors and drawing the nail forward to produce a clicking sound - this is supposed to represent cracking a louse or flea, personified by the person you are insulting. Ah, folk customs...