I'll start with a review of the games I've seen mentioned...
I never owned but I recall seeing Dawnfire in game stores.
Quest of the Ancients is on my shelf, but I've never even finished reading it. I am reminded of a game I used to own that was a D&D-ish game with a black cover with a pentagram on it... got me in trouble with family one vacation as a lad. I swear I replaced my old lost copy years ago, but no idea where it is, or what it was called.
Legionaire: have. Recall having had it in the past as well. Something about aliens that are 'not-human' but still mostly human and mechanically superior to humans... also the dual purpose sci-fi guns. Good times.
Ravenstar: I'm drawing a blank, but it is a maddening blank full of vague notions that I had this once upon a time.
Nightlife: Was going to do a thread on this one actually, having recently found an online supplement from the original author of the game that details some behind the scenes shennanigans he seems to think cost him his chance to make it big... white wolf style... I think he's wrong, sadly. Normie gamers don't want to learn actual rules with statistically modeled numbers, they want pretty tokens. ..
Now for my own contributions, with apologies to our host but I'm not going to his blog to read seven pages of lists in addition to reading this thread...
Maurader 2107, my favorite obscure cyberpunk offering. I used to have every book (all three of them), but I long ago lost my Akuma book and sadly finding a replacement is unlikely.
Does SLA Industries count as obscure? Probably not. Forget I mentioned it.
Valiant Universe RPG? I've seen books on the shelf of the friendly local game store, but honestly I feel like one of the only people that even remember Valiant Comics existed...
StarChilde Publications games: A twofer: Guardians (superheros) and Justifiers (Pre-Furry, antro sci-fi planetary exploration).
Is Millenium's End obscure?
Rather than mention every other mildly uncommon and frequently quite new-ish game I have, I'll close off with the HDL books: Basic Rules, Demongate High, and Perfect Horizon.
If I start digging through boxes, and have a decently objective view of what counts and what doesnt (who has that, anyways?), I could probably be at this all day....