Doubleback was an excellent video game (or so I thought when i was 4) for Tandy machines, released in 1982. The idea was simple. You continually draw this curve on the screen with a joystick. Items like cherries, skates, apples, and horseshoes worth different points appear on the screen. If your line runs into an object you lose a life. Every time you encircle those objects you get their points. And the thing that makes it fun is that if you encircle more than one object (say you encircle n objects), you get n times the point value for every encircled object. Thus for a high score it's really advantageous to wait and let objects build up on the screen. But then it's harder to move around without running into an object! You could also write your name or curse words on the screen, which was cool when i was a little kid.