Alexey Pajitnov made Tetris in 1984 at a Soviet research institute, on a computer that could barely draw it, and he did not earn a rouble from it for years. It has since sold more copies than almost any other game and been ported to essentially every device with a screen.
The design is as close to perfect as games get. Seven shapes, one rule, and a difficulty curve that comes from your own accumulated mistakes rather than anything the game does to you. There's no enemy. You lose to your own earlier decisions.
It's also one of the few games with a documented psychological effect - the Tetris effect, where players see falling blocks when they close their eyes, has been studied properly in sleep research.
The Game Boy version is the one that made it universal, along with a chiptune arrangement of a Russian folk song that is now inseparable from the shapes.
This collection covers the tetrominoes and their arrangements. Still waiting on that long one.