Mind if I throw one in?
if it's bouncing off of one of mine go ahead.
Not really, but the first reminded me of an idea I had for a post-apocalyptic game in which huge asteroids had struck the earth in the middle of World War I. Europe reverted to a feudal system and there were things like knights walking the earth with Brodie helmets and Lee-Enfields, trying to survive the horrors of feudal trench warfare and the Lovecraftian things that were living in the asteroids. Mechanical knowledge from the industrial era was revered, and machines that still worked were cherished as holy relics. I figured the main action of the game could take place on the British mainland. The idea was silly as fuck, but also grim in a way that only this image can properly convey: http://michaelkutsche.deviantart.com/art/The-Trench-94147716
I figured I'd run it in a heavily modified variant of D20 Modern, or maybe Pathfinder, but I couldn't figure out a way to balance it properly or handle pre-decimalized currency, so I scrapped it.