GameSpy writes: "#40: Defender (1981)
In a Nutshell: Spaceship saves humans from alien invasion.
Defender was one of the better Atari 2600 games, even if it was mighty challenging. The action was intense, as you couldn't go very long without using a smart bomb to clear a screen's worth of alien invaders. It's the first game that I can recall with a search-and-rescue objective -- instead of just flying around and shooting bad guys, you were actively searching for the alien landers that abducted your people. You'd shoot down these aliens and swoop in to save the falling humans before they went splat, dropping them off safely in the cityscape below. I remember being very impressed with myself when I learned that you could keep aliens in your stage from abducting any more humans if you kept a rescued hostage on your ship."