Necessary Fiction features some of the best contemporary short fiction out there. This recent addition to their site, a flash piece called "Eskimo Days" by Tawnysha Greene, is excellent. The dark story told through a child's point of view exemplifies how much a writer can do in terms of hinting at a whole life, set of characters and their dysfunction in very little space.
I'm reading a lot of flash right now because next month I'll be teaching a flash fiction workshop for teens and I'm looking for stories we can read as a class. I recently read Kim Chinquee's Oh Baby, which is full of paragraph-length stories that some classify as "prose poems." I thought the book was an enjoyable read, and I've definitely picked out a few pieces to use as examples for the workshop. I'm also reading Amelia Gray's AM/PM, which is just amazing, and quite different from Museum of the Weird. I'm thinking about using a few of her quirky pithy stories as examples as well. I have some so-so anthologies featuring fancy famous writers, but on the whole, they're not really grabbing me. For the most part I've found better work in the online lit mags I read.
If anyone stumbles across any excellent flash pieces or has any recommendations, please send them my way. I'm on the hunt for a range of stories under 1,000 words, contemporary, classic, experimental, traditional, whatever.