and then there is the 'pull my finger' routine-
(a rude bit i didn't know till i was grown up, we had lots of other rude bits, but not 'pull my finger'--one family favorite, for late in the afternoon, at summer family picnics, etc, was to get the kids to get a bucket/pot of water, and to warm it over the almost dead coals, once warm, it was poured over the hands of uncles, cousins, etc, who, having had too much to drink, were lying back on chairs sleeping off the effects--
while the sound of running water can stimulate an urge to go, warm water on your hands creates almost a reflex action!