Now I'm writing an original piece and it is so much MORE fun I don't think I'll ever go back to borrowing the universes of others. It's a lot more work though... But I'm figuring it out. It's been 2 years now and I'm almost done.

Had an idea recently. (Literally "dreamed" up, so to speak.) It's more the kind of story I'd like to read, perhaps. So I write because if I hadn't started I would not have been able to concentrate on anything else.
Writing lots of original stuff too, of course. With Sci-Fi or Fantasy universes.
I have been wanting to make a Smithers/Burns fic for awhile, too.
Good point!
There was a time just a few short centuries ago when original fiction would have been considered inferior. The attitude was something like, "You wrote that? Well whoopee doo -- you just made it up. Are you so hopeless that you have to make up your own stuff instead of finding something interesting to do with the classics?" 
It's strange. I write a lot of original stuff. Including novels which I'm still trying to get published -- gotta rewrite. Anyways...
I s'pose for me that writing fanfiction -- whether it's based on myths or on other stuff -- is more an outlet for obsessions than anything else because otherwise I can't think about anything else (and occasionally can't even focus on my other writing.)
So perhaps it's best described as letting out pressure. Like releasing water from a dam before the whole thing overfills and bursts.
Another question is, what do people do with fanfiction once it's written?
Perhaps the most unique part about my work is that I use my hometown in Southwest Florida as the setting 99% of the time (not to mention I do BIGTIME crossovers). For me, one specific group of characters from a show isn't enough. If I'm going to make a story, it involves a lot of time and mixture.
Overall, I've made some really odd stories, mostly about street racing and remote areas sealed off from their suburban setting. Another common element is war.
Do you,
a) burn it?
b) stick it in a box somewhere, never to be seen again?
c) share it?
d) post it?
Honestly, I have no idea which of these four would be the better option.

If anybody here writes neurodiversity-themed Star Trek fanfics, please let me know -- I have a collection of them on my fic website:
http://www.ventura33.com/neurodiversity

And if I happen to dream up something for your site, I'll certainly give it a go.
First I gotta stick with all the... stuff I'm already working on! and also I was going to post a (possibly better-edited) edition of "Artemis" story on that same site.
Actually I've found most of the fanficcy stuff I read has been really good. (Pleasantly surprised.)
http://www.reviewers-choice.com/lieutena...overy1.htm