Your Friends and Neighbors by
thetreacletart.
Harry Potter. R. Ron/Harry/Hermione.
Harry, Ron, and Hermione move into a new neighborhood. Someone is watching them closely.
I *really* liked this story. All three of the Trio were very well characterized, and the neighbor's characterization was nice and eerie and a very good counterpoint to Harry's. This story has a Twilight-Zone feel, and while I sort of saw the ending coming I couldn't look away until I got there.