I was going to recommend A Change in the Family and The Apprentice but it's pretty clear that thats not what the OP is looking for.

 

To Shape and Change

(Surprised this one hasn't been mentioned yet)

AU. Time Travel. Snape goes back in time, holding the knowledge of what is to come if he fails. No longer holding a grudge, he seeks to shape Harry into the greatest wizard of all time, starting on the day Hagrid took Harry to Diagon Alley. No Horcruxes.

Anarkia

(Not really Snape centric, but it features him quite a bit. It is abandoned though)

Abandonned by his guardians, Harry Potter vanished from existence. Years later, a young man graduates from one of the most elitist and secrete Magical schools and makes his way through Magical societies. Fate or Fatality? Ancient Greeks called it Anarkia.

 

If you liked Pet Project, I would recommend these three:

The Professor's Discretion*by Twelve Years in Azkaban
Takes place during Book 6 and 7 and is somewhat cannon-compliant. Hermione and Snape are working together on a potion project during her sixth year, with Snape exploiting the opportunity to spy on Dumbledore's and Harry's extra-curricular activities. After the events in June, it doesn't take Hermione long to realize that appearances can be deceiving.

Unfinished Business*by Ramos
Hermione Granger dies in a potions accident during her final year at Hogwarts. She's not thrilled when she comes back as a ghost, and really not happy at the idea of spending eternity haunting Snape's classroom. This is very well written, though completely AU to books 6 and 7. It is another story where Snape's potion helps to win the war.

Chaos is Come Again*by*Aashby (rated NC-17)
This story is one of the very few good stories taking place years after Harry's studies at Hogwarts. In many ways this is the very opposite of the sappy epilogue in Book 7. Hermione and Snape are the main characters, with the narrative switching between them each chapter. In essence, this is a good mystery with a bit of very unconventional romance. The story has two endings, with the mystery wrapped up in the first, and the relationship resolved in the epilogue.

 

Hi! Just wondering if you would know why I dont have permission to download this?
thanks in advance!

 

Probably because the post is 2 years old :^)

You can download Soul Play here. It's an archive of deleted fanfiction.