Slick Chick - still one of the most infinitely replayable games I've had the pleasure of playing.
Black Hole - Cold, lifeless, and perfectly realized.
Centaur/Flash Gordon - Requisite Bally '81 alum. One of the best multiball games ever and the best single ball game ever made. If I could only have one game, it would likely be one of these two.
Williams IJ - the ideal compliment to Black Hole: warm, inviting, and also a perfectly realized theme. Even people totally ambivalent to pinball love this game.