This is a really good anime/manga series. It's about a boy named Shindou Hikaru who is the only one who can see Fujiwarano Sai, a ghost who loves to play Go (it's an Asian game with black and white stones and you try to get as much territory as possible on a 19x19 board) and is really great at it. Err, you might not think it's interesting because it's about Go... but it is!! Go check it out. Here's a link.

This anime series currently has 60 subtitled episodes, I think. It's not at all finished. I'll update with new episodes often. I have up to chapter 147 of the manga, which is the middle of volume 17, I think. It's not by far finished...