Just for a few examples: The Tragically Hip. I know Harmonix knows about them! A clothing option is the Tragically Hipsters! As a suggestion for songs: New Orleans Is Sinking, Blow At High Dough, Music @ Work, and so very many others.
Matthew Good (Band): if you want some really good music, you listen to Matthew Good (pun recognized but not intended). Great vocals, some reasonably impressive guitar work, and drums (I can't really rate drums...). Suggestions for really rocking, popular songs: Everything is Automatic, Hello Time Bomb, Oh Be Joyful, Apparitions, Born Losers, Load Me Up, Weapon (WEAPON! If any song should get the full deal, this should be it!), and on and on. Some seriously good stuff here.
Other Canadian bands? Just off the top of my head, perhaps some classic Our Lady Peace (Superman's Dead, anyone?), Sum41, or even, just for giggles, The Constantines (Night-time/Anytime (It's Alright)).
Seriously, though, let's get some Canada action going.









