As the title implies, what is the game you think people are least likely to know of that you've ever owned? Note the owned part! It can be games you no longer have, and it can't be free browser games or something like that
This is a tough one for me, but I guess I'd say...

Tail Concerto - I just bought this game. I'm not even sure how I know of it (and something tells me I don't want to know). It's not from an established series. In fact, outside of a spiritual successor (that was not that successful), it never had a sequel. In fact, before that successor, it was very cheap to get ahold of (but stupid me decided to wait it out), meaning it was probably not well-known. I certainly have only known one person before me who talked about it. It did have a demo disc out there, though, so I'm sure it's not super-obscure. Still, I can't think of any other game I own that a big-time gamer wouldn't know about.
Runner-ups:
The Shadow Heart Series
Ar Tonelico
Atelier Iris
Summon Knight: Swordcraft Story
Since those all had sequels, obviously quite a few people must have known about them, but none of them really talk about them much anymore.

But I eventually learned from my mistakes. 


