I occasionally write, but only paragraphs at a time, and only when inspiration strikes. Generally there are no specific universes, because it all depends on the scene I see in my head.
I also roleplay, both as GM and player. When playing, I play pretty much anything, and when GMing I prefer lovecraftian steampunk or a high-fantasy renaissance setting of my own divising.
Can a river be put under enough pressure to jet straight up for a mile?
How much would licensed necromancy affect the economy of a (European) Renaissance society?
What would the effects of static teleportation points have on a Renaissance society?