Yes, the Bengals were in the Super Bowl in '81 and '88, and lost to the same quarterback both times (Joe Montana and the 49ers). I remember both years (although I only vaguely remember '81... I was 6 at the time, but I remember '88 quite well). Those are the Bengal's only two Super Bowl appearances.

Indianapolis would have a shot at the Super Bowl except for two things... one, they don't do well in the post-season (with me living in the Indy area, I hear about that a lot), and two, the Bengals stand in their way. (I would have liked to see Cincinnati and Indianapolis face each other for the Super Bowl spot in last year's post season, but Carson Palmer's knee injury stopped that dream.)

Speaking of which, I already have my calendar marked for the Dec. 18 meeting between the Colts and the Bengals. I can't go to the game, but I will be watching it on Monday Night Football.

I don't know about Denver, though. I just don't know enough about them, except that they won their division last year. But I will probably agree with your assessment on Miami and San Francisco.