Two classic automata as step-sequencers. Bouncing cells: seed a few cells with directions; each tick they walk one square, and a wall contact plays that wall's note and reflects them — collisions rotate everyone clockwise, so a two-cell seed can evolve a long, unrepeating melody. Game of Life: Conway's rules on a wrapping grid, played a generation per bar — column is time, row is pitch, and crowded cells accent themselves. Every note is locked to the key you choose; export any run as a .mid clip.