On Atari's 40th Birthday: The 10 Greatest Atari 2600 Games
3. Pong. Pong was Atari's first game. It was a painfully simple coin-op tennis game, but the foundation on which the gaming industry stands. Pong on the 2600 required a paddle rather than the iconic joystick. And you could put a whammy on the ball to make it harder for your opponent to get to it.
2. Space Invaders. By the time the VCS came out, Space Invaders was already a monster coin-op hit. VCS systems came with Space Invaders, drawing the arcade user into an inevitable choice to buy the 2600 and bring the game home. You couldn't save games and the scoreboard only went up to 9,999. Unlike modern games, you could not win Space Invaders even by using the double-fire bug. But the game really made the VCS/2600 the beast that it turned out to be.