The Six Virgins

The Casivallan is a warlock who was created by the ancient druids with the intention to sweat the impending invasion of Rome. But the plan backfired. Casivallan sucked the live power of the surrounding and became therefore highly powerful and long living.
He calls for Harry and 6 virgins (Luna, Ginny, Hermione, Daphne, Eloise and Susanne) because Harry’s power burns extremely light but also short. While Harry spends two month with each girl in the past with lots of sex involved, Casivallan remodels Harry so that he can defeat Voldemort and live a life.
DrT writes:

The summer after OotP, Harry spends time with six of his attractive classmates as he goes on a quest through time for the one warlock who has the power to help him defeat Voldemort. Will Harry find love, or at least have a good time? Featuring Ginny, Daphne, Susan, Eloise, Hermione, and Luna in a very unserious tale.

The Story can be read at The Astronomy Tower.
There is also a PDF of the story.

The Companions of the White Warlock

After the killing of Dumbledore, the Runes Professor John Russel helps Harry. During the summer Harry is elected by Higher Magic as White Warlock which brings him more in touch with his Magic. He selects 12 companions for his fight. These are, Russel, Remus, Tonks, Fred, George, Hagrid, Neville, Luna, Ginny, Hermione, Ron and Dobby.
Voldemort allies with The Knight and Companions of Waldpurgis – an eugenics group. Up to the final confrontation several members die: Hagrid, Russel, Fred and Ron.
DrT writes:

The story of Harry’s Sixth and Seventh year in two parts. Part I: HBP as seen through the eyes of Runes Professor John Russell (‚Smoke‚). Part II: Harry, Hermione, and Ron go after the remaining Horcruxes, aided by Luna, Ginny, Neville, Remus, Tonks, and Professor Russell (‚Companions of the White Warlock‘).

The story can be read online at FicWad.
There is also a PDF of the story.

Smoke

Smoke is a prequel to The White Warlock by DrT. The story recounts the happening of the sixth year from the view of the Runes Professor John Russel. He coaches Hermione during that year.
DrT writes himself:

Every night a professor relaxes, thinks, and smokes. Sometimes, a colleague joins him. This night, it is Severus Snape.

The Story can be read at The Dark Arts.
The 11 chapters are also available as PDF.

Recovery and Resolve

This is a short story that tells us what happens when Hermione returns home after her fifth year and has to explain what happend to her parents.
DrT writes:

As Hermione recovers at home from the events at the Department of Mysteries, she first has to inform her parents about the dangers of the magical world, and then has time to think about her future.

The story can be read onlien at Astronomy Tower.
As always there is also a PDF.

Ynulle

This is the ’sequel‘ to „Relations“ and „The Price of Peace“. Voldemort is dead. So is Ron. But Harry has for the first time a possible life and a future. Nevertheless Dumbledoor calls on him and his friends to save the day. They have to man an expedition to an paralell dimension to destroy a crystal sprout, that can be used to control people more completely than Imperius. The destruction goes of without a hitch but there is the memory from Riddles diary, that escaped through the portal into Ynulle instead of „dieing“.
There is also the interesting constellation of Hermine, Harry and Luna.
The story can be read at Schnoogle.
I also made a PDF out of the Story.