The lines are so blurred these days, who can tell? Like gaming used to be pretty niche when I was a kid but now it's pretty mainstream. Stuff like DC/Marvel and sci-fi used to be very much "geek" territory but, again, now pretty mainstream...
My music taste is pretty non-mainstream I suppose but also not really confined to any specific genre or subculture. Also I love nothing more than a good hard rock cover of a mainstream pop song
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