Christian Bale had used Nicolas Cage's performance in this film as inspiration for his role as Patrick Bateman in American Psycho (2000). The characters and films share striking similarities.
Much to the chagrin of director Robert Bierman and Nicolas Cage, there were some scenes removed from the film and multiple cuts of the film suggested. Cage states that those lost scenes represented some of his best work and that he longs for those scenes to be restored someday.
Peter's strange accent is supposed to be a fake accent used by the character because he thinks he sounds more "elegant" and "smarter" (hence the literary agent job). The accent comes and goes throughout the movie and is more prominent when trying to impress people, and less in scenes with people like the psychiatrist.
In the DVD commentary, director Robert Bierman reveals that the furniture and glass Peter (Nicolas Cage) destroys in his apartment after Jackie (Kasi Lemmons) dumps him is all real furniture and glass. The scene could only be shot in one take. Two cameras were on set for the shot and one of them broke. He still can't believe how he allowed Cage to perform such a potentially hazardous stunt.