Okay, I've never posted anything this... er hardcore before on here before, BUT I ABSOLUTELY LOVED FUCKED UP.
This punk band is wicked cool and has been around (and maintained its original members) for ten years now.
Fucked Up kind of straddles the line between "indie rock" (or Twee rock if you're English) and hardcore punk. Not only do these guys collab with members of Circle Jerks and Dead Kennedys, but they team up with Andrew WK and Ezra Koenig and they do it on their fucking christmas album. Sounds pretty "indie" to me.
Oh, and they look like hipster kids.
They're also known for their heavy us of visuals and the first time they played at MTV, they trashed the fucking men's bathroom. Hardcore.
Fucked Up - "The Other Shoe" by AwkwardSound