"Have I not paid? I have given my all to the light, that I might live in dark. I have given to the dark, that I might aid the light."
Just found a lovely little piece on Whitehound's site. It's short and quite magical. The Blade is not really a story, it's just words put together quite poetically, a random musing that creates a picture of Snape that I love. It's by someone called aldalindil, and was written in 2002, which is interesting because she presents the Snape we got to know only in the later books.
Go there now!