Probs, I don't really keep up with my animes/I don't know anyone who likes anime irl, so I just watch whatever I happen to stumble upon. I just haven't seen anyone here talk about it, and this is the only forum I reside in, so it seemed ~underground.~ ^-^ Aaanyways, I might fail at the following, but Princess Tutu is anotha...darkly bizarre, elegantly animated, I loved it.
Don't worry, I'm not that well versed with anime either. XD I too just go by what I stumble upon, although I sometimes will check out an anime show if I have a friend that recommends it to me. FLCL has been mentioned a few times here and I have friends that talked about it, so I'm just going by what I hear.
I don't think many things get underrated as much as they are just completely unknown to a lot of people. A search of Haibane Renmei on this site gave me only 10 results (and two were mine!) despite it being an excellent short series with lots of character-centered, emotionally leaden drama and mystery. Probably it's on account of it being nearly 7 years old so there's no real fanbase anymore, but the big names always push deserving series out of the spotlight.
Yeah, I agree it's likely more that many things aren't unknown and that the big names always get the glory. I admit of tiring of hearing how great Death Note is, even though I do love the show a lot. XD; For the most part if there's a fanbase, there will be people wanting to check it out, like me. :x
Anything made pre-2003 here. :O
Kay, maybe that's an exaggeration, but a lot of the stuff I've seen listed isn't really underrated in any sense. I would say maybe the Buddha manga, but that's by Tezuka and I can't really consider anything by him to be underrated. Maybe Zodiac P.I.? That was a cute little shoujo detective series that was pretty short and could probably count the times I've seen any decent discussion on it here at PC or around the internet...English side at least.
For some reason, the name Zodiac P.I. makes me think of Zodaic the movie. D: Haven't check out Zodiac P.I. though. ^^;
Anyways, guess it depends how one looks at underrated. I too also go by discussions have been going on at PC but I also count things like how many times I have my friends mention this series, the avatars and banners here and other forums (yes, I count that as those are basically showing what fandom you like D: ), and also reviews from various sites.
I agree actually over that 2003 statement to an extent as I don't too many animes made before that time. Also, seems now more people are going with that fandom that's modern or "in," or at least seeing many Code Geass and Pandora Hearts fanbase here. :P Then again, sometimes I don't check what date that anime is made. XD
So yeah, I think it depends on how one sees underrated. Then again, you're more well versed in anime than me and you're most likely right some of the ones mentioned here are probably not that underrated. XD