I've always been a fan of creepy urban legends, so when I heard about Yami Shibai, I simply had to watch it. Each episode is around 5 minutes long, but it works perfectly for the genre, as it leaves you wondering what the heck happened to the characters after the story. It's not the best thing ever, but I'd still recommend watching it if you're looking for something quick. Just a warning though, try to watch it when it's still light outside.