I had the original cartridge, but it was stolen several years ago (a good chunk of my Genesis collection went with it), although I still have my Master System. I also had an Atari 7800 with which I played a bit until it failed and the store didn't want to honor the warranty. Next came my NES and SMS a few years later (with Phantasy Star).
I only had 5 games for the Atari. Space War (A tank game, only with spaceships from a top view perspective), Space Chase (a Space Invaders clone), Othello (some weird board game), Ms PacMan and a cool game about rescuing stranded pilots from aliens in a strange planet, whose name I can't remember. That one was the best of all of them.
The truth is that the Atari was advertised here around 1988 and I had my NES in 1991 as a Christmas present. So even while the Atari is old as hell, I still had the chance to play it as a kid.
I think I need an Atari emulator...
Edit: The Atari game in question about rescuing humans from a planet is called Stargate. I just looked for the rom yesterday. Holy crap... It IS still playable.