I've been playing around with Smashwords for the last couple of weeks, and hope to have a few decent short stories up there in a bit, stuff that editors said was "well written" but didn't fit in their anthologies. I figure why not? List it for ninety-nine cents, throw a few 100% off coupons around, then compile them all into an anthology. That's my plan anyway. We'll see how it goes. I should have my first submission vetted in a few days.
Despite the guide they offer, it's still sort of difficult to perfect everything so that it works on a computer, an ebook reader, smartphones... It's a lot of work to play with pictures sizes and everything.