Let's hear it. I want to go to as many as possible in my life. Lots still left!
No particular order:
Bell Centre - Montreal
Maple Leaf Gardens - Toronto
Scotiabank Arena - Toronto
Keybank Centre - Buffalo
Amalie Arena - Tampa
Joe Louis Arena - Detroit
Little Ceasars Arena - Detroit
Rogers Place - Edmonton
Canadian Tire Centre - Ottawa
United Centre - Chicago
My list starts out exactly as yours does. No United Center though.
Bell Centre - Montreal
Maple Leaf Gardens - Toronto
Scotiabank Arena - Toronto
Keybank Centre - Buffalo
Amalie Arena - Tampa
Joe Louis Arena - Detroit *
Pistons game
Little Ceasars Arena - Detroit
Rogers Place - Edmonton
Canadian Tire Centre - Ottawa
Wild's rink in St.Paul
Saddledome - Calgary
Prudential Center - Jersey
Pepsi Center - Denver *
Frozen 4 final BC vs ND
Amarant - FLA
Sharks rink in SJ
Pens rink in PIT
Oddly enough, I've seen NSH in 4 different cities, Nashville wasn't one of them and I'm not a fan of their team.
Edit::
@jetsforever liked my post and reminded me that I saw a WPG game in their barn as well.
2nd edit: TD Gardens - Boston for a playoff game vs MTL!!! Best experience I've ever had at a rink, so not sure how I forgot it.
Other rivalries I've seen:
-Leafs vs Habs several times in both TOR and MTL
-Red Sox at Yankee Stadium
-Bears in Minnesota on a Monday night
-Vasco di Gama vs Flamenco in Rio de Jeneiro. Definitely the most intense fan experience.