The first (accidental) 3D film, the surprising origin of the Wilhelm Scream, the first damsel in distress, and the first closed captions.
The French film-maker Georges Méliès accidentally created a 3D film in 1905.
The Wilhelm Scream sound effect was voiced by the singer of Purple People Eater.
Mabel Normand was the first actor in film to be tied to railroad tracks, and may have also received the first pie-in-the-face.
Emerson Romero, a deaf silent film star, invented the first closed captions.
The Generalist Academy 
Tied to the tracks, and then, pie in the face? That sounds like quite a movie!