A more modern game that looks worse to me is Big Rigs: Over the Road (http://en.wikipedia.org/wiki/Big_Rigs:_Over_the_Road_Racing). There is basically no game play, no physics, and no real goal (since your opponents don't move from the start line). The video review at http://uk.gamespot.com/pc/driving/bigrigsotrr/review.html is also worth watching to see just how awful this game looks.

I thought it was Desert Bus (http://en.wikipedia.org/wiki/Desert_Bus#Desert_Bus)

a really great music video detailing what Atari did with the cartridges: http://www.youtube.com/watch?v=8Rt_3_bQVJU