The blog Knight2King has a very interesting theory about the denoument of Harry Potter that I had never heard before. So, in the interest of reckless speculation, here's the crux (though not the horcrux!) of it:
If the chess game in PS/SS is a metaphor for the series as a whole, and the pieces the characters play a metaphor for their roles in the series, how do we reconcile the fact that Ron Weasley plays, not only the role of the Knight, but also that of the King - the same role played by Albus Dumbledore in the larger war? Pretty simple, really -- Albus Dumbledore is Ron Weasley.
Rowling is rather predictable in how she introduces various magical concepts to us. She never springs anything on the reader. For instance, we are introduced to the concept of Animagi in chapter one of PS/SS in the form of McGonagall who can turn into a cat, only to have this very same concept used once more in Prisoner of Azkaban (PoA) with the Maurauders and in Goblet of Fire (GoF) with Rita Skeeter. We are introduced to the polyjuice potion in Chamber of Secrets (CoS) with the trio's fruitless attempt to prove that Draco Malfoy is the Heir of Slytherin, only to later have it revealed to be crucial to the plot of GoF with Barty Crouch Jr. posing as Mad Eye Moody. We are introduced to the properties of the phoenix in CoS, and we see them displayed once again in GoF. In CoS, we are introduced to the house elves and their plight, and these downtrodden magical beings take on even more importance in GoF and Order of the Phoenix (OotP). In OotP, we meet a Metamorphmagus... does anyone want to bet against a repeat of this one?
We could go on (parseltongue, prophecies, dreams, magical moving portraits, chocolate frog cards, chess, etc.), but as observant readers already know, JKR doesn't simply use these concepts and toss them aside -- she recycles.
In PoA, we are introduced to the concept of time travel with the Time Turner. So far, we have yet to find another example. It would be unlike JKR to introduce us to something (especially something so big) and not bring it back into the plot with even greater significance. She has given us a subtle reminder of time travel with the time room in the Department of Mysteries in OotP. In a 2000 interview, when asked if Harry would travel in time again, JKR's answer was 'Not telling!' Time travel is coming back... and it will be instrumental to the plot. What does this have to do with Ron, Dumbledore and the chess game? Everything.
Ron, our loyal Knight, will become a time traveler. He will be sent back in time to some point in the 19th century to live out the rest of his days at Albus Dumbledore, our venerable King. The exact mechanics of his journey in time are unclear, though we do believe it is unavoidable, and that it will in fact be the very move that enables Harry's eventual defeat of Voldemort (the checkmate) and that it will also have something to do with the White Queen (Bellatrix). Though you may think us a couple of nutters for making such an outrageous claim, we do indeed have evidence. Lots and lots of evidence.
There's much more evidence behind the link. I have to admit that, on its face, it's a persuasive case, and certainly ties a lot of threads together. Is it true? Well, I guess we'll know on Saturday!