If it would not be so sad that list would be kind of funny:
Massive ejaculation on the face
Subjects involving religion
Food used as sex object
Blindfolds
Hands from 2 different people fingering same girl
Male/male penetration
Transsexuals
Black men-white women themes (so white men - black women is ok?)
Basically it boils down to: Only married couple in missionary position is safe.
There is no freedom of speech in porn
On topic: It seems like there still are some forced sex paysites and a lot of PPV sites, but I think most of them have no affiliate program. ?Army Tales? maybe or ?Naked Preys?.