Depends on what kind of fucked up you mean. A lot of shows like Mirai Nikki or Elfen Lied spam bloody squibs constantly and go for shock value, but eventually you get used to it and the director has to resort to something cheap like killing a puppy to make you feel anything. To my mind that's not really fucked up, it's just edgy for the sake of edgy.
As far as actual fucked up goes, I probably couldn't tell you. Episode 22 of Evangelion is up there for sure, I'll probably just go with that. There's also the end of the Sayonara Zetsubou Sensei manga, but that never got animated, sadly.
What happened with your test tube? I haven't seen whatever that is.
