Okay, whenever I see anime mentioned, I always feel compelled to add my comments.
Witch Hunter Robin is really good, but I still haven't seen the last half of it. I had to stop half way through, 'cause I had been watching it when the fansubs were releasing it and they hadn't finished all the way through at that time. Then I forgot to finish watching... But still pretty impressed with what I've seen. I've seen glimpses of it on Cartoon Network, but because I have an aversion to dubs, I just can't watch it. It ruins it for me. I guess I'm too much of a purist.
Noir also rocks. Still haven't seen it all the way (I have a weird knack for starting series than not finishing them...). But my wall is currently covered in Noir wallscrolls and posters. Mireille and Kirika are just too cool.
Ghost in the Shell is cool, too, but I unfortunately haven't had a chance to see much of it. Didn't get the fansubs when they came out, and have too many other things lined up that I want to buy before I can think about getting it. But I think there's a season 2 and a special that revolves around the Tachikomaz that you like so much.

You might be able to download 'em via bittorrent or search for 'em on irc.
For another cool supernatural powers kind of show/OVA, you guys should check out Read or Die AKA R.O.D. The first part's an OVA (3 eps), and the story revolves around a character named Yomiko Readman AKA The Paper. Her power basically has to do with... well... paper.

She can manipulate it almost anyway she wants, which is really neat. And though she's a little flighty at times, she proves to be a very capable secret agent type person. The whole feel of the anime gives off a James Bond meets supernatural anime type feel. Very cool. And recently released in Japan was the OVA's sequel, Read or Dream, which is a fun and, at times, very intense continuation of the storyline. You can find it on bittorrent by a couple of different fansubbers, though I'd recommend AonE 'cause they did a really good job translating everything.
Ack! Okay, I think I've typed enough. Sorry, anime's one of my BIG obsessions, so once I get going it's hard to stop me. =P
Okay, I can't help it... a few more quick, random recommendations: Utena (for crazy, what the hell?? factor), Maria-sama ga Miteru (kinda slow-paced shoujo story, but with lots of fun characters. My current obsession), Haibane Renmei (from creators of Lain, NieA Under 7, etc), Tsukikage Ran (Xena as a samurai!), Azumanga Daioh (cute!!!)... okay, I'm stopping now. Yep, really stopping... really... *pulls herself away from keyboard*
-Mandy (yes, I am an otaku!

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