I was just checking out Psycho again and noticed a couple new things for the first time.
1. Skull superimposed -- at the end of Psycho, just before the dissolve to the vehicle being pulled from the swamp, there's a close-up of Norman's face, and briefly there's a superimposed image of his mother's skull over his face.
2. Sam Loomis -- In Psycho the boyfriend of Marion Crane was Sam Loomis. And in Halloween 78 that's the name of Donald Pleasence's character.
I'm sure you all already knew about those, but I didn't.