The famous line I ever liked is from the movie The Matrix where Morpheus says to Neo "Throughout human history, we have been dependent on machines to survive. Fate, it seems, is not without a sense of irony."
for me its harry lime in the third man. Looking down from the big wheel in the vienna prata he says if some of those dots down there stopped moving, would anyone really mind? its terrifying in its banality but brilliently played