I personally love nothing more than a Great Loyalty Oath Crusade.

Linked from Richard Carrier is this piece:

Avoid telling racist or sexist or homophobic jokes, unless perhaps if they are empowering because the target of the joke is the racist or sexist or homophobe. Don’t ever target specific real people with jokes or suggestions about rape or anal self-abuse.

I really hate it when someone tells me not to do something in a way that really makes me want to do it. I mean, I never thought of literally telling someone to self-abuse themselves anally before reading this post.