The 8th Annual Writer's Digest Short Short Story Competition (ISBN 1425175864)

I'm kind of biased...:
..considering I wrote one of the stories in the book (#18, "Typecasting"), but I definitely give the overall book a five-star rating. It's not easy telling a full realized story in fifteen-hundred words or less, but it's a good exercise in tightening your work and trimming the fat, and the other twenty-four stories in this collection are all good examples of that done quite well.