The primary source of inspiration for the setting of Exiled Future is the Avernum computer games. Which I first played back when they were just called Exile. Made by the game company Spiderweb Software who makes very good and fun fantasy RPG games.
The rules are a hodgepodge of ideas and rules I’ve grabbed from other places. The main foundation is Lamentations of the Flame Princess. Though almost nothing of that framework remains at this point it still remains a good foundation for old-school Dungeons & Dragons.
Huge pieces of rules and major inspiration have come from the blogs Goblin Punch, False Machine, Playing D&D With Porn Stars, and Pens & Paper. With plenty of influence from bits and pieces of other gaming blogs in smaller pieces that are too numerous (and not always remembered) to mention individually.
I’ve found that my creativity and effort works best when I’m mixing or modifying other people’s work. Which means there isn’t a lot that is straight up original work. Which would suck if I was selling this, but I don’t see it as a problem for a D&D campaign where so much of the actual creativity and enjoyment is what happens during play at the table, not the text and ideas on the page.