I remember being absolutely smitten by the RPG
The Lord of the Rings: The Third Age. Great combat, fine characters, an amazing OST which was partially taken from the movies, and the rest of the OST was made to resemble their tracks (I think). It's not that it was unpopular, but it didn't really get amazing reviews, except from IGN, it seems (8.5/10).
Then there's
Lost Odyssey, which was ignored by many people, probably because it wasn't called Final Fantasy -- even though it pretty much was. Square Enix haven't made a real Final Fantasy game in years, which isn't surprising since the creator of FF, along with the composer, left a long time ago to found Mistwalker. Aside from that, the director of the best FF games has been demoted to producer, meaning he has no real influence on the final product.
LOTR: War in the North was surprisingly fun, and while not great, still not worth ignoring.
And uuh... yeah, I don't remember 95% of the games I've owned, and I sold them all, so... oh well