Anime Thread

[Mutsukki]

I don't really know about Battle Spirits, that's true, but as far as I know Midori no Hibi was very popular when it came out, especially by the fact that the main character has a loli puppet for a hand. Even truer (?) for Arakawa Under the Bridge (if that's what you meant by "Under the Bridge"), since it was a manga popular enough to become an anime with two seasons.

I know you probably meant western popularity, but really, there are hardly "non-mainstream" anime, I guess it depends on the genre/studio you follow or tend to like. It's hard to find "obscure" things because hardly anyone would put their time and effort on subbing and translating obscure anime and not advertising it everywhere.