As I read Harry Potter and the Deathly Hallows right up until bedtime last night, I had HP7-related dreams all night. I finished the book today. If you are concerned about encountering spoilers or unbridled nerdiness, please avoid the text below:

1. I dreamt that Hermione was killed by Bellatrix Lestrange. This was a terrible scene, with Ron sobbing over the body and so on. I am very relieved that this didn't happen in the novel.

2. I also dreamt that Harry was a seventh Horcrux, and he had to be martyred in order to defeat Voldemort. Although this snippet ended up being true, the dream differed from the book in several ways. Harry didn't have anything left in him after his murder; he was truly dead. No conversation with Dumbledore, no second chance, nothing.

Because all HP novels are written in a third person limited (to Harry, of course) style, his death changed the feel of narrative quite a bit. There was a switch to third person omniscient. Harry's funeral was a memorable affair, where he was heralded as a savior for his killing of Voldemort via the ultimate sacrifice. There was also a great deal of focus on Ron's reaction to Hermione's and Harry's deaths.
They were buried side by side in Godric's Hollow.

This was not a happy ending, but it worked in some ways. Harry and Hermione were remembered as great heroes. Ron's love went unrequited, a far cry from the sunshine and daisies epilogue of the actual book. And the wizarding world was still saved by Harry, though in a far more depressing manner.