>>10672<Manga Koe no Katachi
Rabbit Doubt
I Am Hero
Gantz
All I can think of off the top of my head.
The first two are one shots and are pretty good imo. I I Am Hero is on-going and pretty good, even though I haven't kept up with it in a while. Gantz was one of my favorites, but it finished a long time ago. It does kind of get bad near the end.