Apple declined to carry a comic-book adaptation of James Joyce's Ulysses for the iPad because one panel showed a man's penis: "While the first chapter of the book, the one now at iTunes, doesn't contain 'offensive language' our comic does have frank nudity. Something we figured we might have to pixelate or cover with 'fig leaves'. But Apple's policy prohibits even that. So we were forced to either scrap the idea of moving to the tablet with Apple or re-design our pages."
Joyce's Ulysses Banned Again--by Apple, Not the Government (Thanks, sixfngers!)