It's a three way tie for me. The Big Lebowski, Dazed and Confused, and Friday. All of which are instant classics and I could watch them 100 times and not be bored. Especially if I was stoned. I've never laughed harder about these classic lines from each of the movies...
The Big Lebowksi: Walter Sobchak: You want a toe? I can get you a toe, believe me. There are ways, Dude. You don't wanna know about it, believe me.
The Dude: Yeah, but Walter...
Walter Sobchak: Hell, I can get you a toe by 3 o'clock this afternoon... with nail polish. These fucking amateurs...
Friday: "Well round here, between Normandie and Western, we call this here a little twenty twen twen... "
Dazed and Confused: Slater: "Behind every good man there is a woman, and that woman was Martha Washington, man, and everyday George would come home, she would have a big fat bowl waiting for him, man, when he come in the door, man, she was a hip, hip, hip lady, man."