Tetris has been implemented in Conway's Game of Life (external)
Over four years ago, a challenge was posed on the Programming Puzzles & Code Golf Stack Exchange: Build a working game of Tetris in Conway’s Game of Life (GoL). Yesterday, an incredibly dedicated team of seven posted a working solution that is just fantastic to read about. I am flabbergasted by the work that went into this, and what these folks achieved. Starting with the concept of a metapixel – essentially a giant block of GoL tiles that can be programmed to behave like a single GoL cell, but with any ruleset – they developed wiring, logic gates, an ALU, a RISC architecture, an assembly language, a higher-level language, and finally (for now) a working game of Tetris. Not the first example of advanced computation in GoL (Wireworld is well known), but almost certainly the largest in scope and likely the best-documented as well. I linked to the Stack Exchange page, and if you have any knowledge of GoL, logic gates, or low-level computing, the multiple write-ups are incredibly clear and fascinating.