Marty McFly: Calvin? Why do you keep calling me Calvin?
Lorraine Baines: Well, that is your name, isn't it? Calvin Klein? It's written all over your underwear.
When Biff and his goon friends are in Biff's car, as they chase Marty on his borrowed 'skateboard', the car's rearview mirror repeatedly disappears and reappears, and the side mirror changes from round to square repeatedly.
The farm where Marty arrives in 1955 belongs to a man called Peabody, and he calls his son Sherman; both names are a tribute to "Sherman and Mr. Peabody", two cartoon time travellers.