[Elladan and Elrohir]

Of course, Tolkien had chosen the title long before he knew that Frodo had called his book TDotLotRatRotK.

It is quite interesting that Tolkien uses this title, especially considering that Sauron never actually makes an appearance in the book (he appears to Pippin in the palantir, but we only hear about it after the fact; and of course we see his realization and wrath when Frodo claims the Ring, but this isn't really an appearance). It's an unusual, but I think in this case an excellent, literary device to have the main antagonist never appear in the book; but it is quite interesting that the book is then named for him.

Really, though, there aren't very many more options, for titles that is. "The Quest of the Ring," I suppose, is a possibility, but somehow that isn't as mysterious and alluring as "The Lord of the Rings." Somehow that title -- to me, anyway -- implies something dark, and epic. It did even before I had read the book.