Can anyone recommend other similar movies?

I cant think of anything really similar, unless you mean anime targeted at older audience.

Id definitely recommend WOlf's Rain and works of Satoshi Kon (Paranoia Agent, Paprika), Baccano! as well as Basilisk.

Akira.
Elfen Lied.
Fist of the North Star show and animated movie.
Golgo 13 The Professional.
Urotsukidoji 1 & 2.

"Killer Klowns from Outer Space? Holy S***"

Ninja Scroll is a good one, and perhaps Highlander from the same director, although it is nowhere near as good.

In addition to what I posted previously, was also thinking about Gungrave, Claymore and Texhnolyze (once you get past episode 7/8 it starts making sense)... I was looking for something like Vampire Hunter, but I guess there is nothing quite like it.

If you liked Wicked City, i recommend to watch Demon City: Shinjuku. Also depending on what "features" you seek in animes.. I mean if you like Vampire Hunter D then you would propably also like "Berserk". Its violent but i think the story is unique.

My mother got a kick out of this series:
http://en.wikipedia.org/wiki/Nightwalker_midnight_detective

Anything by Kawajiri is a pure animation feast. He directed another novel of Kikuchi's called A Wind Named Amnesia. By far one of the neatest stories I have ever come across. Rare to find but it worth the time. Also as mentioned before, his Highlander anime movie was pretty cool too.