I wrote Conway's Game of Life simulation on an attiny85 with an SSD1306-driven OLED display.
The fun part was to manage the display (a 128x64 one) in a dynamic way by using the small amount of SRAM available. I ended up writting a custom SSD1306 driver for the micro, so it allows the user to create (and modify) a 32x16 grid that can be stored in the internal SRAM and then translated into "big pixels” in the real 128x64 OLED screen.