Wordrunner eChapbooks publishes an annual themed anthology, taking submissions just prior to publication, but also then publishes two e-chapbooks of fiction each year. While they have a submission fee, they are also a paying market (with a better return than I've been getting for playing the lottery lately). "Our aim is to make high quality writing available free or at very low cost, much like the original chapbooks that were hawked in the streets of 18th and 19th century London for pennies," the editors note. Yet web publishing opens up all kinds of new options for digital-aged readers: "In many issues, hyperlinks to photos, videos, background articles, maps, poetry, and artwork add new dimensions to the online reading experience."
The current chapbook is Ovenbirds and Other Stories by Dorene O'Brien, with a full archive of previous e-chapbooks and anthologies going back to 2008. Submissions for the spring anthology will open January 1 with submissions for the e-chapbook fiction series running from May 1 - June 30. Lots of time to get your manuscripts ready!