Monster is a great anime, but for Berserk I preferred read the manga.
Slayers rulez, but the Italian version was censored
If you like Elfen Lied, you have watch Higurashi no Naku Koro Ni.
For manga, you can read Narutaru (pay attention, you can find a censored version, it's a very violent manga) or Bokura No (do not watch the anime, you must reading the manga, THAT is the real Bokura No)
Another good anime is AIR, beautiful but sad...