I got to thinking about Romeo and Juliet, how it's not considered by critics one of Shakespeare's greatest plays, but how it still has a huge portion of his most memorable lines. You kiss by the book, or What light through yonder window breaks? Etc.
Anyway, then I started thinking about the finest sentences ever composed in English. I think Shakespeare had a greater mastery of the language than anyone else has or will -- That which we call a rose, by any other name would smell as sweet seems to be a contender. But there are tons of great English poets and a lot of famous sentences in the great canon of English literature. The last line of The Great Gatsby, or of A Tale of Two Cities. The most famous lines from Nabokov. And then there's the entire collection of English song lyrics, of which there are millions.
So what do you all think?
EDIT: so many fantastic answers.