I've never been that great with short form fiction. Everything I write tends to grow longer and longer, and even my short stories tend to claw their way towards 10k words pretty easily. This happened just recently, and now that story is undergoing some dramatic restructuring in an attempt to bring the word count back under control.
My published (free) short Le Morte d'Arthur is one of the best I've written, largely because it stayed short. This is one of the few occasions where I didn't leave out many of the ideas I'd had for the story - it was always as succinct as it turned out. Not my usual MO. Generally there are a thousand little details I want to expand.
Ironically, a lot of the fans of that story have told me they'd like to see a longer piece featuring Morte. Hm.
Now, in the last week, I've jotted down two stories that managed to weigh in at under a thousand words and still work well. One I will be rewriting in a slightly less brief form, but I don't anticipate it will expand too greatly in word count. Might even stay under 1k, though the concept behind it could probably drive a novel. The other one probably only works as a short piece.
I haven't yet been able to pin down a set of traits for short stories that only truly work as shorts. It's a question I've been puzzling over for awhile now, and quite frankly I haven't made much headway. Anybody know of a good discussion of the topic?