I remember one of the very first sectors I ever did I had to distribute magazines (the good ol' days) and a pax in first class being a smart *ss asked me for a Playboy. Innocently I turned to him and said 'I don't have a Playboy but I can find you a boy to play with.' I was only turning the words around but he went quiet very quickly and turned away promptly to avoid my gaze!
Regarding with the clicking of the fingers I had an American lady travelling with her husband click her fingers at me. I just turned to her and started clicking back at her and asked her what I can do for her. She was really embarrassed and her husband chastised her for her actions. She apologised and I ended up having a nice chat to both of them during the trip.
Ciao