An Atari 800 joystick, which was basically the same as the 2600 one. Many evenings spent playing Zaxxon, Miner 2049er, and so on, as well as simple games typed in from magazines.

Then I bought an NES and didn't look back. Super Mario Bros. was way more advanced, not only in terms of graphics but also the fluidity of movement and the game pad design. And it was more fun!