Not as well known as Loompanics, but Paladin Press may have more of an effect on the grey area of publishing because of the effect of a court case involving one of its books. Paladin specializes in controversial and unusual material, and they revel in producing books about private investigation, revenge, exotic weapons, explosives, and other fun subjects. But the fun stopped when Paladin was sued because one of its books, Hit Man, was included as evidence in a murder case.
If you've been following First Amendment and free-speech cases, you'll know about the Hit Man case. It seems that a psycho used the book as an instruction manual for murdering his victims. He actually butchered three people before he was caught (which shows how crappy the book is – it didn't tell him how to get away with it).
Paladin Press, the publishers of the book Hit Man, were sued by the family of a murder victim because the murderer used the book Hit Man as an instruction manual for his crime. It obviously wasn't a very good manual, because he was still caught and convicted. But the lawsuit against the publisher threatened to have a serious affect on freedom of speech, because it would make publishers liable for the material they publish if the material is "criminal."
Paladin Press was prepared to take the case to the Supreme Court, but their insurance company decided it would be cheaper to settle with a judgement of about $5 million. Paladin has removed the book from its list of available titles.