There are some great memorable lines in film industry, it's hard if possible to pick only few, but pick we shall. Please do add more to it, a reason why you like that particular line rather than simply making a list.

"Say Hello to My Little Friend" (Scarface) - I'll be honest here, I never saw Scarface, but this line is epic. You can use it on so many occasions, best part of it others will know what you're referring at.

"I am the Law" (Judge Dredd) - It doesn't get cheesier than this, but goddamn I love it. It almost makes me wanna watch Judge Dredd again, almost.

"Do You Feel Lucky" (Dirty Harry) - This line is but an icing on the cake because the entire speech was bloody awesome.

"It's Just Been Revoked" (Lethal Weapon 2) - It's something you expect from Riggs, but coming from Murtaugh makes it even better. One of the best endings, actually, best comeback ever.

"Say What Again" (Pulp Fiction) - It wouldn't matter if I went with something from "Snakes on a Plane", "Shaft", or any other movie for that matter because everything sounds equally awesome when spoken by Samuel L. Jackson. I wish this guy would yell at me.

I could add million more, but this will have to do for now.