- Lauging at a joke that you weren't supposed to understand.
- Catching someone complain about the presence of foriegn devils, turning around, and agreeing with him completely. "Yeah, I thought this was such a nice place, but I wish they would do something about all these dirty foriengers."
- Haggling with someone in English, then switching to target language and saying 'Okay, enough of the tourist prices, I'll give you half or I'm leaving'.
- Making a joke in a foriegn language that would make no sense in English.
and my personal favorite
- Catching someone tell you one thing in English, then try and double cross you when he talks to his buddy next to him. Relpying with "Don't worry, it's safe to speak xxxx in front of me, I don't understand a word" in xxxx, and watching the phrase register with one guy but not the other made months of effort pay off. (It also helped in avoiding a nasty double crossing, but that's another story entirely)