I used to love the Wings/Leafs games, but since the re-alignment, that was one that lost meaning.
Bears/Packers is not much anymore since the teams can't seem to be competitive at the same time anymore
Yanks/Red sox is persistent. Dodgers/Giants and all other baseball rivalries just don't do anything for me. To me a great rivalry involves physical play (football/hockey). Only the Yanks/Red Sox rivalry and the 80's Lakers/Celtics were worthwhile to me. That's just my opinion though.
What is unique is the Avs/Wings to me is the fact that most rivalries are related to teams proximity or divisions (which Sandra's examples exemplify). Wings Avs was born out of competition and physical play. Both teams fans have just an insane amount of dislike for the other team. Much like the Mich/OSU rivalry, the whole season can sometimes be judged by the fans on how you play 1 team.