Okay, I want to know about the homebrew systems that ya'll use. Why? Because I'm writing a game for a custom setting I made. I had originally planned to do it in d20M, but then decided it didin't completely fit, I'd have to do so much tailoring I might as well make up a new game. And I like creating new games, it's fun.
I've found a SFRPG by Psion (it can be found here, but haven't seen anything by the rest of you.
As for my game, it's a relatively standard angels vs. demons thing with humans caught in the middle. Stats run from 1 to 3, skills from 0 to 2. There are 9 stats, divided into 3 categories: Physical has Strength, Toughness, and Dexterity; Mental has Intelligence, Awareness, and Charisma; and Spiritual has Faith, Fate, and Willpower. There are 14 pretty broad normal skills and then 6 magic skills. Task resolution is roll a number of d8s equal to stat+skill, take highest, if any other dice come up 7 or 8 they add +1 to the check result, compare vs. difficutly (easy=4, average=6, hard=8, straining=10, practically impossible=12).
So, what are your systems/settings like?

As for my game, it's a relatively standard angels vs. demons thing with humans caught in the middle. Stats run from 1 to 3, skills from 0 to 2. There are 9 stats, divided into 3 categories: Physical has Strength, Toughness, and Dexterity; Mental has Intelligence, Awareness, and Charisma; and Spiritual has Faith, Fate, and Willpower. There are 14 pretty broad normal skills and then 6 magic skills. Task resolution is roll a number of d8s equal to stat+skill, take highest, if any other dice come up 7 or 8 they add +1 to the check result, compare vs. difficutly (easy=4, average=6, hard=8, straining=10, practically impossible=12).
So, what are your systems/settings like?