Ed Catmull (later a Pixar founder) and Fred Parke (later a professor) made a remarkable film in 1972. They made a 3D model of Ed's hand, then animated the hand moving in 3D space, including clenching into a fist. There are also other models, including a very primitive human face. While it seems very crude to us today, this was extremely groundbreaking stuff in 1972 -- and it led directly to the technology used in 3D animation today.
According to some accounts, this is the first digital 3D-rendered film ever made. What you see in this film is pioneering work in math, computer science, and art -- all in one. Have a look:
Read up on the film at Robby Ingebretsen's blog -- he talks about the film, its provenance, and how his father was involved with the project. Interesting note from that blog entry: the film was rendered directly to 8mm film stock.