My favorite finger-sucking scene in a movie (only I would have a fave finger-sucking scene

) is from Leaving Las Vegas, when a drunk Nic Cage pays a hooker to give him a bj in an alley...cut to her sucking...and you're completely shocked (are they actually showing it????) and then you realize she's sucking the wedding ring off his finger. She steals it and runs off while he passes out in the alley!
A great mind trick the director plays on you!