Now this I like. I usually don't think about all the ghost stories that are out there in Japanese literature, but let me just say that there are a lot. Growing up for a while in Japan, I was introduced to the vast panoply of these beasts through video games, manga, animation, and stories (although mostly through Gegege no kitaro).
Looking through the tubbypaws blog, I came across a beast that I haven't seen in quite a while: rokuro-kubi. After searching for her online, I came across her entry on the Obakemono Project. This has got to be one of the more fun databases of Japanese ghosts, goblins, and demons out there (at least in English), and ranks up there for fun and interest with Encyclopedia Mythica.