thought for today

i'm sitting in the student center of my school right now, a place that is most generally populated by underclassmen and avoided by upperclassmen due to its constant noise. it seemed pretty quiet today so i wandered in. as i'm doing some homework and checking some blogs, the kid next to me, a sophomore whose remarkable resemblence to macaulay culkin has earned him the clever nickname of "the macaulay culkin kid" is writing about the catcher in the rye, one of my favorite books. i know that he is writing about the catcher in the rye, because about one minute after i sat down he said loudly, "holden caulfield is such a faggot!" he continued this for 20 minutes until he left, with variations such as this is gay, faggot-ass this, faggot-ass that, and so on. needless to say, this drove me crazy. however, i didn't know what to do. i could have just snapped at him to shut up, but that would have made him angry. i could have explained to him why i took offense, but when i've tried this in the past during conversations with guys my age, they usually just ignore me. and yes, it would be great if he thought about what i said and stopped using homophobic slurs, but the reality is that there are many people who use this kind of language. my question is, what is the best response to this? and not just in this particular instance, i'd like to address the everyday types of prejudice (racism, sexism, classism, etc.) that you know you should combat, but you just can't see the point in it. i'm not sure if i'm articulating this correctly, but if anyone does have a suggestion to this, please comment and let me know.