First of all, and before I begin describing the basis of this ruleset, due credits where credits are due.
The game system I'm working on is actually an expansion of the sketch rules created by Andy Foster (Heresy Miniatures) for his "Netherhells" game (link for that embryo). These are based on Heroquest, and as that game they are intended for a boardgame. Yet I saw a lot of potential for true rpgs, just by adding some rules for skills, and different levels for heroes.
Then I came across Pelgrane Press' "Trail of Cthulhu" game, which was like a gust of fresh air in the modern investigative games, and just one step beyond the purely narrative games. That gave me a lot of food for thought regarding what simple rule systems could achieve.
I also put my hands on Margaret Weiss Productions' "Serenity" and "Battlestar Galactica", two rpgs that shared the same rules system, called "codex", which added yet another elegant simple rule system, this time for a science fiction setting, and not too dissimilar to what was already on my mind.
So I was left there, somewhat dazed and confused with so many inputs, wondering how could I turn all that into a single coherent system. Then I lost steam and got derailed by other things for some months. Finally I decided to take this project back on track, and it appears that my subconscious mind had been working on it all this time, as I promptly realized that it was pretty easy to merge the three systems I've mentioned.
What will follow is an hybrid, maybe abominable but hopefully fun.