No groaning, it's a fic, and it applies.
A Year Like None Other is written by Aspen In The Sunlight.
This fic takes the premise of Snape becoming Harry's father and gives it an interesting twist. From the complete destruction of Harry's magical power, to the incorporation of Draco as Harry's adopted brother, the character interaction is very deep.
Instead of simply throwing things together and forcing them out of canon to make them work, the author pulls each character's problems into a realistic light and shows them dealing with them. The depth of the character interaction is amazingly realistic. The characters often do not get along, and occasionally there are major clashes of views. In each part of this story, the author's skill with descriptions and suspense makes you feel as though you are experiencing the story firsthand. As the story rolls on, you start to feel as though you know the characters, and have done so for a long period of time.
In short, it's amazing, and can be found here. (http://archive.skyehawke.com/story.php?no=5036&PHPSESSID=c31aa7e33792666734067840fdc0dd0b)