I'm not too sure I like the results I got on this one, but it's a pretty cool site!

Check out Labs.Five.Com, this site takes your profile on Facebook and analyzes it to see who on your friend's list is most similar to you.

The site uses posts to see how outgoing, agreeable, neurotic, and conscientious you are. It then takes a look at your friend's posts for the same thing.

My posts came across mainly neurotic according to this. I'm not sure how I feel about that.