Five Moments of Doubt (http://www.fanfiction.net/s/3675387/1/Five_Moments_of_Doubt) is a great genfic favorite of mine and, if you don't mind fic about Eileen Prince(-Snape), one for sorrow (http://lilith-morgana.livejournal.com/244459.html) is hertbreakingly beautiful (it was written before Deathly Harrows was released but it holds up fine to the later canon).