I remember reading (but can't find in my memories) an RPS story with the premise that Supernatural was on non-network TV, so could have graphic, adult content. This story was told from Jared's point of view about filming the scene where Sam finally goes completely darkside and rapes Dean. The last line was something about Jared hearing Jensen make the sound of Dean breaking...

Anyway, it was awesome and I need to read it again. Thanks for any help finding this.

FOUND - "To Destroy Me and You" by esohpe http://esohpe.livejournal.com/56477.html