I saw one strange ranking of one low quality site in some very competitive niche and i don't know how to explain its ranking. It has 34 backlinks showing in yahoo, only the home page indexed with very little content on it - about 50-100 words of text and one image and the domain is also not aged. I don't want to post it publicly here because i know some people don't like this but if someone wants to check it i will send him through PM.