In both the book and movie:
- The business card comparison scene (especially in the movie) is pretty hilarious:
[Looking at Paul Allen's business card]Look at that subtle off-white coloring. The tasteful thickness of it. Oh my God, it even has a watermark!
- From the same scene in the book: "...we also go to the same barber, although I have a slightly better haircut."
- The cash machine that says "Feed me a stray cat".
- A scene in the book (filmed but omitted from the movie) features Patrick painfully trying to be hip and familiar with a Rastafarian, calling him "Marley" and saying "...yeah, we be jammin'..." to himself after being brushed off.
- Here it is from the book:
I stick out my hand at a crooked angle, trying to mimic a rapper. "Hey," I say. "I'm fresh. The freshest, y'know— like, uh, def— the deffest." I take a sip of champagne. "You know— def."
To prove this I spot a black guy with dreadlocks and I walk up to him and exclaim "Rasta Man!" and hold out my hand, anticipating a high-five.
- Here it is from the book:
In the book:
- Bateman's red snapper pizza rant in the book is pretty funny too, especially since it comes totally out of left field:
"No one wants the fucking red snapper pizza! A pizza should be yeasty and slightly bready and have a cheesy crust! The crusts here are too fucking thin because the shithead chef who cooks here overbakes everything! The pizza is dried out and brittle!"
- And then later, when Bateman is forced to eat his words because Donald Trump says he likes the pizza in question.
- Which is in turn Hilarious in Hindsight when Jon Stewart ridiculed Trump for taking Sarah Palin to a budget franchise pizza place, passing it off to her and her family as "Authentic New York Pizza".
- "Could you keep it down? I'm trying to do drugs!"
- The chapter where Bateman and his associates are trying to organize a dinner in a restaurant using conference call and mess everything up.
- 'I quickly stand, brushing him off, and and when I think his outburst has subsided and he's able to walk away, Luis grabs my right ankle and tries to hold on as I'm leaving Barney's and I end up dragging him along for six feet before I have to kick him in the face, while smiling helplessly at a couple who are browsing near the sock department.'
- In the first chapter of the book, Timothy Price (Patrick's associate) is reading a newspaper and commenting on all the terrible headlines:
"In one issue... in one issue... let's see here... strangled models, babies thrown from tenement rooftops, kids killed in the subway, a Communist rally, Mafia boss wiped out, Nazis, baseball players with AIDS, more Mafia shit, gridlock, the homeless, various maniacs, faggots dropping like flies in the streets, surrogate mothers, the cancellation of a soap opera..."
- There's a fake TV talk show (think Maury Povich) that Patrick occasionally watches called The Patty Winters Show. The topics he mentions start out as pretty normal and mundane (Autism), but they quickly descend into nonsense ("Dwarf Tossing" "A boy who fell in love with a box of soap", and "UFOs That Kill"). Later on, when Patrick's lost all touch with reality, the show has Bigfoot on as a guest, who Patrick claimed was "surprisingly articulate and charming", and finally...
"On The Patty Winters Show this morning a Cheerio sat in a very small chair and was interviewed for close to an hour."
- Bateman playing with the little daughter of one of his associates, offering her his American Express card: "I'm shaking my head, talking in a high-pitched baby voice, squeezing her chin, waving the card in front of her face, cooing, 'Yes I'm a total psychopathic murderer, oh yes I am, I like to kill people, oh yes I do, honey, little sweetie pie, yes I do...'"
- Patrick makes a bunch of obscene phone calls:
"I'm a corporate raider," I whispered lasciviously into the cordless phone. "I orchestrate hostile takeovers. What do you think of that?" and I would pause before making sucking noises, freakish piglike grunts, and then ask, "Huh, bitch?" Most of the time I could tell they were frightened and this pleased me greatly, enabled me to maintain a strong, pulsing erection for the duration of the calls, until one of the girls, Hilary Wallace, asked, unfazed, "Dad, is that you?" and whatever enthusiasm I'd built up plummeted.
- Along with a teller demanding Patrick "Kill the President!" and "Feed me a Stray Cat", Patrick also hallucinates that a park bench chased him down the street for several blocks. He recounts that with total sincerity.
- Patrick becomes very happy when he manages to buy a box of cereal by paying with an expired coupon. He tries to whistle "Hip to be Square" while he eats them and then proceeds to run up and down the streets, screaming "like a banshee", his open coat flying like a cape.
- In one commercial on TV, a man says to his wife, "Hey, you're right... this margarine really does taste better than shit."
In the movie:
- The scene in which Bateman reels off all manner of memorized observations regarding the musical styling of Huey Lewis and the News - all the while preparing to murder Paul Allen.
- The Chainsaw Scene, especially the part where he drops the chainsaw down a flight of stairs onto her. He actually tries tracking his target from above by holding the chainsaw out with one arm and circling it around and around. And he hits the target.
- "Their lyrics are as positive and affirmative as anything I've heard in rock. Christy, get down on your knees so Sabrina can see your asshole... Phil Collins' solo career seems to be more commercial and therefore more satisfying, in a narrower way. Especially songs like In the Air Tonight and Against All Odds - Sabrina, don't just stare at it, eat it."
- At the beginning of this scene, when Patrick is blathering on about his favourite music, there's a blink-and-you-miss-it example as the two prostitutes clearly share an irritated "Jesus, can you believe this asshole?" glance with each other.
- Bateman's surprised look when he shoots at a police car and it explodes.
- Bateman making ridiculous faces as he flexes his muscles at himself in the mirror, while he's having sex with two prostitutes, as Phil Collins's "Sussudio" plays.
- In the movie, when the hooker is trying to escape from Bateman's apartment, she trips and falls, and Bateman catches up with her... only for him to stop, grab her leg, and start biting on it. She stares at him numbly for a moment, then slowly draws her other leg back and kicks him square in the face. In what should be a horrifying scene, the audience laughs their collective asses off.
- "Not the face! You bitch!"
- After Luis mistakes Patrick's attempt to strangle him as an attempt to come on to him, Patrick scrubs his hands furiously in the sink... without taking his gloves off.
Luis: Patrick!Patrick: WHAT IS IT?!Luis: Where are you going?Patrick: I have to return some video tapes.
- This scene:
- Ten times funnier as Patrick awkwardly leaves, he again hears Luis call him and he turns to see Luis doing the 'Call me!' signal, which only causes Patrick to leave in embarrassment.
- Thanks to certain similarities between the characters of Patrick Bateman and Bruce Wayne, quite a bit of metahumor is to be had at the casting choice of Christian Bale in The Dark Knight Saga, complete with Youtube mashups of the two characters to create such classics as "The Dark American Psycho Knight".
- Or the meta-humor that comes from the guy who played Batman straight up murdering the guy who would go on to play The Joker.
- Patrick's Paul Allen impersonation when he leaves a voicemail on his dead colleague's answering machine.