Katsudou Shashin

Both are some of the earliest film works from Japan, both are over a century old, and they pioneered animation today as we know it. 

Very short pieces of animation. Maybe the shortest out there. Both do a good job of presenting the meaning of something too. The titles are self-explanatory as to what they present. 

The first 2D animation and the first 3D animation known in Japan. Sad that Bio-Sensor is way more obscure. 

Short, old early japanese animation done with experimental purposes way before the concept of anime series existed. 

Two shorts in where the only thing that happens is some letters being written on screen.