Atlanta Nights by Travis Tea -- written as a sting, to see whether a certain publisher, claiming to be highly selective, would publish this turkey, despite each chapter being written by a different writer and then assembled in the order returned to the organizer of the hoax. (I was #10.) You can read the details here. Plus a PDF of the novel itself.
And recently, I have learned that a dramatic reading of it was podcasted! You can view the chapters here and discover how terribly bad a book can be.