OK, I have a few I've messed around with.

The fantasy setting I've used for my Dungeon World games is fairly standard from an on-the-ground perspective, but I thought the structure I created for it was kind of neat.
The world is roughly flat and circular, with a fiery source of heat to the center, a cold (ultimately frozen) ocean around the edge, solid earth below, and an expanse of air above (thus including all the classical elements). The titans (beings of embodied chaos defeated long ago by the gods) are imprisoned below the earth.
There are a lot of gods, but they are categorized and themed fairly simply. There are 7 main "good" deities who created the world and act to preserve the balances of nature and human society; they're themed after the Seven Heavenly Virtues (and there's a sub-cycle of four representing the four seasons). There are 7 "evil" deities who represent disruptions to or things outside of the natural order, themed after the Seven Deadly Sins (and again, a sub-cycle of four, based on the Horsemen of the Apocalypse). There are four "neutral" elemental gods who maintain the integrity of the material world. And there are a number of minor deities who are ascended mortals of various stripes, usually tied to one or other of the greater deities.
I gave some thought as to why people would worship the various deities, including the "evil" ones, and how they might be interpreted differently or have different aspects attached to them in different cultures.

Another one I haven't had much chance to play in is an anime-inspired cyberpunk anthro setting called Eigen City, drawing elements from Bubblegum Crisis, Shadowrun, JoJo's Bizarre Adventure, and Zootopia, among others. (...and I was definitely working on it long before that one OotS comic about the various other worlds the gods made :P ) Even though it's basically a mashup of tropes and setting elements I like drawing and writing about, I have quite a few details written out (and quite a few intentional blanks to be filled in later).
It's the last city left on the planet Rhea after an environmental collapse, protected from the polluted atmosphere by a vast energy shield wall. The city was built by alien beings known as the Galactics to preserve what was left of the planet's population around three or four generations past. The city is a place where reality seems somewhat "thin", where corporations war in the shadows and people can bond with spirits that grant them superpowers. It's a place where just about anything can happen.
I actually have a setting document written up with Fate setting aspects as I got to play in a game based around it for a short time. I'm actually thinking of trying to start a different Fate Accelerated game using the setting.
(As of the writing of this, my forum avatar is the character I was playing, Vixie "Silver" Reinhardt and her agathion, JAM Project.)