Mad Scientist/Researcher!Harry
don't know if thats been done before but I would like to see a story where harry takes a crap on the prophecy and just studies magic for the sake of it. he could then evolve into a sort of mad scientist, that is obsessed with his work. think frankenstein only with magic. to be able to afford his expensieve experiments he would have to sell his magical skill to wizarding society, sell some of his experiments or just wreak havoc in the muggle world.
the fullfillment of the prophecy could act as a subplot that sends voldemort and him into battle. through his self-experiments, rituals and his study of strange magics and the like, harry could have an edge over the deatheater.

rules:
- no wandless magic
- harry must not become an idiot who dodges around every spell thrown at him, hes a wizard and not spider man
- while he is gone studying, the rest of magical britain must go to hell so as to make the light side desperate to bring him back into the fight
- harry must make some sorts of experiments on himself ( potion accidents, artificial limbs ..you name it )

 

http://forums.darklordpotter.net/showthread.php?t=2446
Practically the same thing. I suppose your's is kind of different, but it will eventually boil down to the same thing.