Actually, let me expound on that--I'm offended not by words but by intent. Someone could call me a word they made up, and if I can tell the intent is malicious, that there's hate behind that word, I'll be offended.

Throwing around racial slurs as a joke, so long as it's obvious that you're not using the words to hurt or hate, has never bothered me. That's not naive. In fact, I think it's rather mature.