Weirdest books ever

I want something so absurd your jaw hangs open while reading. After reading the wasp factory I realised I get so much more invested in the weird, darkest, most grotesque works. I've read one by murakami and plan on reading more of his. But I want something so ridiculous and strange. The one's that make you wonder who in the hell comes up with this stuff and still has the audacity to publish it. Any ideas?