I remember watching film adaptation of this novel several years ago. I was impressed by the relentless pace, seemingly random camera work and an underlying atmosphere of madness.
I had the same feelings when I finally reached for Palahniuk's work. Knowing the story (I do remember the film very well despite seeing it only once years ago), I paid more attention to elements that indicate deteriorating mental state of the protagonist. I have to admit they're interwoven with the plot really well. At the same time I felt a bit overwhelmed by all the anger and negativity present throughout the whole novel. Getting through it wasn't easy but in the end I felt good about it and found new level of appreciation for the film adaptation.