Alfred Hitchcock's Psycho is honestly my most favorite film, ever. Not only did it break new ground in term of storytelling and marketing (the female lead we were led to believe died when the film barely started!), but its ability to do so much with so little; Hitchcock used his TV show crew to film this feature, even the now iconic score by Bernard Herrmann, was written with just the string section of an orchestra.
And that title sequence by Saul Bass—the graphic designer in me is drooling.