What's your favorite comedy?

So, Jason's movie trivia thing got me thinking about doing something along similar lines here. But then I couldn't come up with anything so I decided to ask everyone what to list their favorite comedy and why. The why is the important part here. You can't just say "Fast Times at Ridgemont High 'cause I like Phoebe Cates' hooters". Okay, well maybe you can say that but I'm looking for a bit more than "hooters".

For me, it's always been Blazing Saddles. I'm a big fan of comedies, as evidenced by my DVD collection which is made of up of mostly comedies. So why Blazing Saddles? Let's make a list:

The dialogue. Hands down, the best dialogue in a comedy, ever. The funny thing about the script is that Richard Pryor had a hand in writing it, but he focused mainly on writing the white actors parts, whereas Mel Brooks wrote most of the black actors parts. And the black actors have the best lines. And the majority of the lines from this movie are still quotable after 25 years.

Comedic setup. I've always hated comedies where the situations are forced (e.g., two people have a conversation about the grim reaper knocking on their door and then the doorbell rings). Everything in this movie flows perfectly, even when it breaks the fourth wall (literally and figuratively) at the end. The timing and delivery of each scene results in maximum humorous payoff.

The actors. With a cast that includes Gene Wilder, Mel Brooks, Madeline Kahn and Slim Pickens, how can you go wrong? The actors don't just inhabit their roles, they breathe them; to the extent that you actually believe these people are like this in real life.

The storyline. You couldn't make Blazing Saddles today. In this PC perfect, racially sensitive world we live in, Blazing Saddles would be protested before they shot one frame of film. But 25 years ago, nobody batted an eyelash. And that's sad because this movie actually lands a punch square in the nose on racial stereotypes by poking fun at some of the more outlandish ideas that people have about race. (One of my favorite lines that wouldn't make it today: Bart, the black sheriff, sees a friend of his for the first time since being carted off to jail. The friend says, "They said you was hung!" Bart answers, "And they was right!")

There are others that came in so close it wasn't funny (Clerks, Search for the Holy Grail, The Jerk) but Blazing Saddles takes the cake for me in terms of an all-encompassing comedy. So what is everyone else's favorite comedy?