Here is my favourite part:
Giving a gift with your left hand...
What you think you are saying:
"Thank you very much for letting me marry your daughter. She is very beautiful. In gratitude, please accept this dainty, yet tuneful instrument. Did I mention that I'm left-handed?"
What you are actually saying:
"Thank you very much for letting me marry your daughter. She is the most worthless heap of dog vomit I have ever encountered, and I dearly wish that she would die. In gratitude, please accept a generous portion of my own effluence. Did I mention that I hate you?"
http://www.cracked.com/article_16335_7-innocent-gestures-that-can-get-you-killed-overseas.html