"The trouble I have with deeming something "obscure" is that it's relative to the context that you're comparing the music to. Like if I mentioned The Chariot, mewithoutyou, Living Sacrifice, Zao, Becoming the Archetype or Underoath, many people may say "yes those are obscure", but someone who's familiar with the "Christian alternative/metal whatever scene" would recognize if not, be familiar with most of those names. So while none of my IRL friends (except for my brother) know/care about Opeth, Between the Buried and Me etc...I don't really want to label those two in particular obscure since I know in the prog community, these guys are increasingly well known (especially Opeth). They're also on well known labels (Roadrunner and Victory respectively). But if I have to give an answer I'll say Intronaut. "
I'm labeling obscure in the sense of how well known it is around my area. In which case bands like The Chariot, Opeth, BTBAM are really only listened to or known by a select group of people.
Although thanks to Rock Band 2, a fair amount of people know the song Prequel to the Sequel by BTBAM >___>.
Hybrid Theory is a solid album. Meteora is not very enjoyable (Breaking the Habit is the standout, along with Nobody's Listening), Minutes to Midnight is shit (Songs like No More Sorrow are listenable, but I could never get into that album).
So overall, I don't have a problem with their music really. But I rarely, if ever, listen to them anymore.
I've yet to meet anyone (in real life) who has heard of Windmills by the Ocean, Celeste, Jesu, or Earth. A lot of other bands I listen to I rarely find people (like Mastodon, Between the Buried and Me, Opeth) but have a few fans.