The Secret History of Fantasy is a 19-story collection of what I'm given to understand is unusual or different fantasy, along with a couple nonfiction essays about the genre as a whole (and of course, the forward by Peter Beagle). Taken as a whole, it was a varied and sometimes fascinating read, though as in any short story collection, there were a few that just flat didn't work for me.
To start things off - I finally found a Gaiman story that I liked! It's like a miracle! His "Snow, Glass, Apples" is, as one might surmise from the title, a new take on the old story of Snow White, with a lovely, creepy and disturbing inversion on the story. Reading it left me unsettled in a really good way, but I imagine that for some people it might be a little too unsettling. Not for Gaiman fans though - this is stylistically pretty much in his bailiwick.
Another of my favorites was (surprise surprise) Octavia Butler's "The Book of Martha" in which a woman is given the opportunity of a lifetime - of all lifetimes - by god. I think this story had the most complete, most real character to me. Martha acted how I could see myself acting, presented with this impossible situation.
A lot of the stories I enjoyed a lot but they didn't hit the level of these two - Ancestor Money by Maureen F. MgHugh was a lovely character piece; Lady of Skulls (Patricia McKillip) and John Uskglass and the Cumbrian Charcoal Burner (Susanna Clarke) both had that sort of fairy-tale feel I love; 26 Monkeys, Also The Abyss by Kij Johnson was a delight to read prose-wise and actually made the "it's magic" explanation work; Gregory Maguire's Scarecrow was another fun inversion; and Mythago Wood by Robert Holdstock had a wonderfully ponderous mythology that reminded me, oddly, of The Perilous Gard (one of my favorite books).
Also, two of the stories in this I love but I'd read before, in the Stephen King and Peter Beagle stories. Both are really great, showcasing some of what makes each of these writers among my favorites ever.
Beyond this, I don't want to talk too much about individual stories, because while all of them were enjoyable, none of the rest really grabbed me. Some it was the writing style, and some just the story itself. In two cases, I'm not actually sure what the "fantasy" angle was meant to be at all.
But this was a really good, really strong collection and if you like your fantasy a bit unusual there will be something in here for you.