I thought everyone already knew what bjhtn said about the "Wiener" issue. The odd thing about it is that the city's name is probably the only thing not changed dramatically by the Viennese accent (which is quite pleasant, I think).

Along with the various Anglicized meanings of "Wiener", I'd also add an antiquated (ca. 1950's) connotation. If someone was dubbed a "Weener", it meant someone nerdy, small, geeky, probably annoying and a few other negative things. In America, it often has the meaning "penis" but particularly, a small one, as opposed to other slang words for large ones. This is probably due to the hors d'oeuvre item "Viennese sausage", known for their tiny size. Also called "cocktail franks", I can only think of one person who ever used this term to describe a man's penis. This was Tom Hanks in the film "Volunteers", as he insulted a Chinese warlord who held him captive. A bold move!

It's interesting that many of these also derive from German words, often by way of Yiddish/German.