It's a tough choice but if I had to choose one it would have to be the Big Lebowski as it is probably the most re-watchable and cos' John Goodman is so awesome in this film. So many greats to choose from though....I have yet to see Burn after Reading as it's not released here yet.

As awesome as No Country for Old Men, Miller's Crossing and to a lesser extent Blood Simple are I still think they excell best in comedy/black homour category.
"Do you see what happens when you fuck a stranger in the ass?!"

The dude and co. take the prize, I think.
Burn after reading was pretty good. but i like No Country best.

Lets blaze, put this in your sig if you want to get high
Quote by tona_107
Burn after reading is ridiculous.

Burn After Reading was one big, totally awesome cluster-fuck.

Top award still goes to The Big Lebowski though.

"Donny, you're out of your element!!"
Quote by Beakwithteeth
O Brother Where Art Thou

I didn't like this film as much as their others...it seemed a little too 'cartoony' for me.
No Country for Old Men...

the only one I have seen (I need to see more movies)
^This post was probably sarcastic


Chief Executive Officer of Music Games of THE ULTIMATE-GUITAR GAMING FORCE
The Dude Abides

Quote by iceman95
Fiddler is a god!!!! omg that's a good movie
Burn After Reading was absolutely hilarious.

I'd say it ties with Beg Lebowski, although Fargo is a close second, with Raising Arizona and O Brother, Where Art Thou? as third. I have yet to see No Country for Old Men, or any of their other films though.
The only two I've seen are No Country and saw Burn After Reading today, it was pretty funny... I loved Brad Pitt getting shot, I didn't see it coming at all (it's pretty obvious in hindsight). Not sure which is my favourite though..

The Big Lebowski totally and O brother where art thou i just think its a lot different to all their others
She Had An Abortion That She Made Me Pay For