Is there a such thing as, Reverse Racism?

With the racial tension being what it is today, it has me thinking about racism, and whether or not reverse racism exist. I often hear caucasians use this term when describing "angry/outspoken blacks. Conversely, I've heard blacks say that it's impossible for blacks to be racist? How do you define a racist? Let's talk about it on Darryel's Daily Dialogue, "where positive words, manifest positive action."