Poppy Z Brite / Scotland's "Extreme Porn" Bill
Poppy Z Brite, author of erotic horror, would be another example - one of her short stories (His Mouth Will Taste Of Wormwood) features a bit about a dog giving oral sex to a woman. Not to mention her novel Exquisite Corpse, which features necrophilia and sex killings.
In practice, people might not be locked up for possessing physical published books, but that just shows the inconsistency if people are arrested for possessing similar writings that either they downloaded from a BDSM erotica site, or were their own personal fantasies.
Not mentioned in the article is the progress of Scotland's version of the "extreme porn" bill. This bill is already broader than England's version, and a selection of "Women's" groups are coordinating a lobbying effort against the Government to extend it even further, in particular demanding that non-photographic images be covered (they cite Second Life as an example, and this would presumably cover cartoons and drawings also). They stress that they see this law as merely being a "first step" - the end game is to see possession of all porn criminalised.
Have a read of the responses at http://www.scottish.parliament.uk/s3/committees/justice/inquiries/CriminalJusticeandLicensing/ju-criminaljustice-evid.htm , if you fancy seeing the kind of anti-porn crusade that's going on here.