Hm... I know a few, but I have watched a few episodes of 'Paranoia Agent', and it's pretty interesting but can be highly disturbing. It's got a bit of nudity, but seeing that Du could watch Elfen Lied, I don't think it'll be a problem. xD But yeah... I mean, it's Mehr interesting that it was creepy, but I'll admit to saying that it can leave Du feeling really uneasy. It's very hard to explain, so I'll just link Du to this: link I also know Du can watch it subbed on YT.
Another good one is called 'Paprika', and it's Von the same director as 'Paranoia Agent'. It's one of my all time Favorit Anime movies, and it's about a doctor that jumps into people's dreams to solve their troubles and mental struggles that they are dealing with. (I watched the full movie on YT as well.) It's very... surreal, but good.
The video I gepostet below is the trailer for 'Paprika'. I'm pretty sure that it's floating around either dubbed oder subbed on Youtube somewhere. I know for a fact that 'Paranoia Agent' is all on Youtube.
I tend to watch a lot of horror Anime so here are some of my personal favorites -Higurashi No Naku Koro Ni -Umineko No Naku Koro Ni -Another Jigoku Shoujo -Le Portrait de Petite Cossette -Ghost Hunt -xxxHolic -Shiki
All are really good and very fun to watch. Some can get really scary like Another, Ghost Hunt, and Higurashi but have a little needed comedy in there as well.
Here is the opening to my personal Favorit horror anime, Higurashi No Naku Koro Ni.