 If you liked
Serial Experiments Lain
|
 ...then you might like
Gantz
|
It is similar that characters die and go "to another place". In Serial Experiments Lain they go to the Wired and in Gantz to a room where they must complete missions to kill Aliens.
Both also deal well with the psychology of the characters and their plots.
Watching it, you can see more similarities between the two. The biggest difference is that Gantz is an action anime.