okr on 25 November 2010
It's Suikoden Tierkreis. I don't know if it's the most underrated DS game, as Darth said, but definitely the most misspelled one. 
Tier = animal, Kreis = circle, Tierkreis = German for zodiac.
As the best ones were already mentioned, let me add three not so popular ones on DS which I really liked
- Nostalgia
- Final Fantasy: The 4 Heroes of Light
- The Wizard of Oz: Beyond the Yellow Brick Road
Hopefully Lufia will be good as well (I have yet to buy the import version) and I'm sure Golden Sun will be great.
and on PSP
- Ys Seven
I thought I'd have to import this one as well, until I accidentally found out yesterday that it's available on the EU PSN. My first Ys, great game so far.
