To say that American Psycho is one of the funniest movies I've seen is probably a testament to my sick sense of humor. It's full of satire and insanity and plenty of dark humor. The odd thing is I can't seem to come up with enough things to say about it because it can be summed up so simply. I know people criticize Christian Bale's acting, but had he reversed roles with Heath Ledger in the Dark Knight, I'm convinced he would have been able to pull it off.The unmitigated violence and sex is completely appropriate because it only seems to add to the humor of this psychotic character.
On the flip side, there's also this sense of baring witness to Bateman's neurosis firsthand. In the end of the film, you aren't sure whether anything you just saw actually happened, or if it was just a deranged fantasy. All the characters are painted as two-dimensionally as they would in a comedy and some of the events are so bizarre and difficult to explain that you question reality at any level. It is that surrealism, however, that allows you to disconnect enough to laugh at things you'd normally feel sick watching.
The social commentary on 80s yuppie culture is priceless as well. After spending ten minutes with Batemen and his circle of friends, it's no wonder he starts them off. American Psycho is just one of those movies that can pull off all these seemingly incongruous elements together and still be entertaining. Sure it'll leave you scratching your head thinking if you choose to, but you could also just sit down and turn your brain off and still enjoy it.