Cars can be used as massmurdering weapons when you drive into crowd so cars are probably bad. :D

http://www.goodreads.com/book/show/8374702-the-erotic-engine

From cave painting to photography to the internet, pornography has always been at the cutting edge in adopting and exploiting new developments in mass communication. And in so doing, it has helped to promote and propel those developments in ways that are rarely acknowledged.