Miller - Budweiser
Oracle - Microsoft
Ford - Chevy
Oooops … back to sports …
Minnesota Fats - Willie Mosconi (Pocket Billards)
Gryffindor vs. Slytherin (Quidditch)
Scooby Doobies vs. Yogi Yahooeys vs. Really Rottens (Laff-a-lympics)
White Spy vs. Black Spy (Mad Magazine)
Bills vs Dolphins (NFL)
Squish the fish!!!
Yes I know they are not fish.
Georgia grad checking in. Tech thinks this is a rivalry; UGA doesn’t pay much mind.
The big rivalry, especially in football, is Georgia - Florida. The game is played on neutral territory (in Jacksonville) every year.
Point #4 ends all discussion since 4/5 of the league is expansion teams. Also, other than Pheonix what teams qualify under point 5?
Anything in Northern California v. Anything in Southern California…
It transends sports, politics, lifestyle, resources,…etc.
Not to the Packer fans it’s not. Heck, the Vikings didn’t even exist the first time I saw the Pack play the Bears on TV.
Qadgop the Packerfan. 
Browns-Steelers, at least before the original Browns became the Baltimore Ravens. Do the expansion Browns even have rivals?
Michigan - Ohio State anything!
Remeber the ESPN commercial with the girl and guy sitting on the couch saying “I love you’s” and the guy wore an Ohio State shirt and the girl wore a Michigan shirt? (or vice-versa)
The tag line was “Without sport, this wouldn’t be disgusting”.
If they do, the rivals are lucky, the Browns suck.
Ravens-Steelers.
International football rivalries:
England vs Germany
Brazil vs Argentina
Mexico vs. U.S. (although it’s a lot bigger deal in Mexico than the U.S.)
Maybe when the Nordiques moved from Quebec to Denver to become the Avalanche? I could never understand the Nordiques, they just couldn’t get it together even though they had some great teams. Didn’t they win the Cup the year after they moved to Denver?
The Nordiques had excellent attendance, but a crappy, old arena. They had a great number of young future stars, but league salaries kept rising to ridiculous levels. They drafted Eric Lindros and traded him for six players, two high draft picks, and pitiful amount of cash. How were they going to pay all their players, and get a new arena (which the city wouldn’t help them with).
The hockey fans in Colorado may have deserved a team, but they didn’t get their own team. They stole one from another city. While I was happy to see some of the former Nordiques win the Cup with the Avalanche, I couldn’t understand the people in Quebec who celebrated Colorado’s win.
Damn you Colorado! Damn you all to hell!
Anyhoo, as for current rivalries in hockey…
Ottawa/Toronto is a big one… Buffalo/Toronto and Phildelphia/Toronto aren’t bad either… No matter how good or bad either team is playing, Islanders and Rangers fans absolutely hate each other… Calgary/Edmonton is a classic… Boston/Montreal was a classic, but is currently on hiatus… Quebec/Montreal was an excellent rivalry, even when the Nordiques were a last-place team…
Colorado/Detroit had a very mean rivalry going on for a while… Nashville drives Detroit crazy, and Predators fans hate all the transplated Michiganders who cheer the Wings in Nashville… And the so-called “Predwings” fans are just idiots… Nashville isn’t very fond of Chicago either…
Have the games between Dallas and Minnesota shown any potential? I know if I played for the Wild, I’d love to nail it to the Stars… I have no idea why Seattle (the first American city to ever win the Stanley Cup) never got an NHL team. They could have been a good close rival for Vancouver to bang heads with… How do Los Angeles, San Jose and Anaheim get along? Likewise, how about Florida and Tampa Bay?
Anyhoo…
No, no, in hockey, it’s the New York Islanders and the New York Rangers, hands down.
It’s the only rivalry I’ve seen in the NHL that results in the arena management having to erect a metal gate in the hall between the team’s locker rooms when they play each other.
PS: The Rangers suck!
Is Denver a ‘tourist city’?
Rangers v Celtic
Aberdeen v Rangers
Man Utd v Liverpool
Man Utd v Arsenal
England v Germany
England v Argentina
Scotland v England
Boca Juniors v River Plate
In the whole of NBA history, I’d have to go with Lakers-Celtics. We haven’t seen anything like Magic-Bird before or since.
I used to have season tickets for the Blackhawks, back in the early 90’s when they had something that resembled a hockey team. In those days I would have to say the Minnesota North Stars were our biggest rival (or, the “no stars” as we called them). At that time Minnesota had Dino Ciccarelli and Basil McRae, I lost my voice more than once yelling at those two.
The craziest hockey brawl I ever saw was during the pre-game warm up at the Chicago Stadium with the North Stars. Both teams were on the ice when somehow a fight broke out between Basil McRae and Stu Grimson. Before long, there were several fights going on between Chicago and Minnesota players. Mind you, there are no officials or coaches present during the pre-game warm up, no one was there to stop the impending riot. It’s a rare sight to see 25 players from both teams fighting on a rink littered with 100 gloves and 50 sticks they had abandon.
This went on for at least 10 minutes, one or two fights would settle down, then two or three more would erupt. There were fans standing on top of the boards trying to pop the glass out so they could get involved. Finally the head coach from Minnesota appeared on the ice, he got punched a couple times, then the fight broke up. About 5 seconds into the actual game, there was some pushing and shoving going on, the ref called like 4 game misconducts and that was the end of that. Ahhhh, now THAT’S hockey. 
Rangers - Celtic