The most racist comedy I have seen recently was Spike Lee's "Kings of Comedy." It made me very angry to see comedy routines built around the themes of how blacks are stupid, how corporal punishment is funny, and how sexism is funny. This, in case you haven't seen it, is comedy delivered by black comedians to a black audience. It's on video too now.
So far as I can see, racism is a poison that totally permeates this culture. (I am not saying it does not exist in other cultures.) It is possible to do comedy and raise consciousness about racism: Dick Gregory used to do it, Whoppi Goldberg used to do it. What Spike Lee and others are doing right now is beyond me.
Joanna Bujes