I just recently discovered Flash writing--not the genre, but writing it. The best thing about it for me was that I could experiment with different styles or general ways of writing wo having to sustain it over a longer pieced. If I experiment with a longer piece, then decide I can't stand it, it feels like time wasted (though it's actually not since I was writing). But with a short piece, there's no big loss if I later decide I don't like "the experiment."