This is a different one. Last night while I was feeling like crap I read the completed fanfic, Severus' Dreams, by Paganaidd. I've read the whole series and it's one of my favorites. The series starts with Dudley's Memories, continues with Snape's Memories, and concludes with Severus' Dreams. If you want to read the stories, I'd read them in just that order.
The gist of the series is that Dudley has become a social worker and deals with abused children. When he comes across a child with obvious magic, he ends up calling on Harry to help a young boy named Tim. By the events in Severus' Dreams, Tim has been adopted by the Potters and is in his first year at Hogwarts. (Completely non-canon, which is usually a deal-breaker for me, but it's done so well, I love it.) In the last story, which is what I'll talk about right now, the story opens at Christmas 1997. The Golden Trio is on the run from Death Eaters and Snape is the Headmaster at Hogwarts. All of the teachers are shunning him and he's feeling quite depressed and lonely. Madam Pomfrey sees this (she has reasons for thinking there's more going on than just Snape being a Death Eater) and gives him a gift that sends him forward in time as a sort-of spirit in Tim's body. Obviously, there's more going on and Snape has to find his way back to his time.
The author deals with issues such as child and sexual abuse, traumatic brain injury, and psychological disorders in the series, so it's fittingly tagged as an "angst" story (another deal-breaker, but, again, she did it extremely well). This is not a fluffy story. It is a damned good story, especially when you take the whole series into account. Obviously, I don't want to give too much away, but she also doesn't bludgeon the reader to death with those issues. As Alka-Seltzer made famous, "Try it, you'll like it!"
Paganaidd has a wordpress page where she's writing original fiction. I haven't read the novel yet, but it sounds interesting.