Well, one of my grandfathers is racist. We actually were concerned one time because my cousin found out that she was pregnant, and the father was black. She had already dumped the guy, so my grandfather never knew him, but everyone was concerned about what would happen when he saw the child. Needless to say, it isn't particularly thrilling to be glad that a child from an interracial couple was born white enough to not anger her racist great grandfather. Funnily enough, she's actually my grandfather's favorite great-grandchild, at least if what I can gather from what my cousins say on Facebook is any good.
But as for a specific instance, it has to be when a guy was complaining to me about my manager. After his ranting, which included plenty of "*****" comments, he then said, "You know what you call people like her? You call them a ******." Now if that's all he said, I would have just passed that off as another angry old guy ranting (you get plenty of them at Walmart). Then he said, "And you know that things in this country have only gone down hill since they came along." I don't think I have ever been a situation where I came closer to being fired than then. I would have kicked him out of the store, but I was working outside when he started talking to me, and by then, kicking him out wouldn't work.