I voted Homebrew, as my current home campaign is a homebrew world that heavily overlays the Points of Light campaign setting fluff (i.e. deities, empire names, etc.). For D&D, I have always made my own settings, often grabbing ideas from existing settings and modules. The only published setting I've ever been excited enough about to run a game in is Eberron.
For non-D&D games, I either have a unique concept and try to find a system that I can modify to work with the concept and play it out. Alternately, I use the standard setting of the game (i.e. Deadlands, Fading Suns, etc.) if it's a game I want to try out or the system is integrated with the setting.