I'm wondering about what the downside to publishing a book of previously available (on my blog and/or on a now-defunct flash website that was a non-paying market) flash fiction stories on Kindle or similar e-pub would be. I've got copyright free and clear; the ones published on the third-party website were only granted one-time, non-exclusive rights to electronic publication. Basically, I could put together 5-6000 words of flash. Since I write horror, I think that thirteen stories would be a nice round number, and some of them would be new to the world (not counting beta-readers). The one thing I can think of is that I should perhaps wait until I've finished a longer piece (novel I hope) that I'm working on, then toss the flash out there for ninety-nine cents as a teaser. Any downsides to this? I'm not kidding myself that I'll become the horror Andy Weir (although it would be nice), but since the stories are a) flash fiction, and b) "used", I can't see any publisher wanting to take them on, no matter how creepy they are.
I don't see a downside, based on my understanding of the situation. Probably not a big upside, either, but... I can't see it being a problem for you.