I published a story ("Gray Ebenezer") in March with Penumbra eMag. I enjoyed the experience, and found everyone involved to be extremely professional. Penumbra is, however, the only place I've published so far that is behind a paywall--which is to say, they don't give away their fiction.
Except, right now, they do! Not all of it, but they've recently revamped their site and in order to introduce new readers of to their brand, they're offering their first twelve issues for free! (These are from 2011 and 2012, scroll down the page to find them.)
I highly recommend checking them out. :-) And now, it doesn't cost you a dime.