List of International Faux Pas
I don't know if this list is faux real (sorry- I had to do it! It's more like I'm not sure how complete it is). Via Boing Boing, there is a list on Wikipedia of faux pas in different countries.
It is a very entertaining list, but my favorite is one for Hungary: Simple generalizations about Eastern Europe are considered incorrect and confusing Hungarians with Russians is even more incorrect. I think it would be nice if the US had a widely held belief that making simple generalizations about any group of people would be a faux pas.