Heart and Soul by Sillimaure. Potter AU -- Harry's trial before the Wizengamot goes much more badly than in canon, and the only thing that can help him is the execution of a long-standing marriage contract that betroths him to Fleur Delacour. The events that grow out of this act send Harry's fifth year in directions wildly different from canon.
The story is long-winded, but has a lot of things going for it, including a) a radically different version of horcruxes that both is worse than and which complicates things far more than in canon; b) a means of killing Voldemort that I don't think I've ever seen, anywhere at all in fanfic; c) a plot and characters which address, answer, and sometimes do all those things readers of both OotP and fanfic frequently point out as obvious and only sensible. Among many other things. Give it a try -- it's slow to start (and to play out) but worth it.
-- Bob
---------
Then the horns kicked in...
...and my shoes began to squeak.
The story is long-winded, but has a lot of things going for it, including a) a radically different version of horcruxes that both is worse than and which complicates things far more than in canon; b) a means of killing Voldemort that I don't think I've ever seen, anywhere at all in fanfic; c) a plot and characters which address, answer, and sometimes do all those things readers of both OotP and fanfic frequently point out as obvious and only sensible. Among many other things. Give it a try -- it's slow to start (and to play out) but worth it.
-- Bob
---------
Then the horns kicked in...
...and my shoes began to squeak.