There are two kinds of writing challenges, for me: The ones I only need to do once, to prove I can do them, and the ones I come back to over and over again. NaNoWriMo and NaPoWriMo are the latter, for me. I don't win NaNo every year, but by god, I try. And I've done NaPoWriMo every April since 2007.
I'm not sure, right now, how I feel about Story-a-Day. I enjoyed doing it. I'm glad I "won" it this year, after losing my train of thought halfway through last year.
And it reminded me of what these things almost always remind me of - I feel better when I'm writing. I know that. It's such a simple thing, but it can keep me out, or pull me out, of a bad mindset. Yet it's so easy to forget when I am in that depressed space.
A couple of people lately have asked me if I write things to submit, for publishing, and generally the answer has been no. I write things to share. I post them here, or they end up on Smashwords, or both. I'm thinking about it, though.