PROPOSAL

You're in a foreign city. The language barrier is daunting or perhaps impenetrable, but you're surrounded by people who have some formal education and/or cross-cultural exposure. You have to take a shit. You don't want the indignity of pointing at your own ass in a frantic way or shouting something like, "WHERE ... IS ... THE ... TOILET!" This is a communications issue that the human race should've settled a long time ago. There's an international sign for choking, and it seems to work quite well, so I argue that there should be one for I will soon soil my pants if you don't direct me to the proper facilities. Below you'll see my suggested gesture, which is built off the idea of "number two" being a synonym for "shit." It also employs a double-pound for emphasis:

Let's consider it a "beta" test for now. I'm not sure sure about the universality of the gesture. But I'm certain that there are plenty of smart people who can help me refine this. In any case, such a nonverbal expression could be quite handy and discreet, even in situations where everybody already speaks the same language.

NOTE: It's possible that this gesture could be misinterpreted as, "I urge you to play a game of Rock-Paper-Scissors with me."