Desdichado
Hero
Darkness and Dread and Grim Tales still do exactly that; they are systemless rules machines. As is Unearthed Arcana, come to think of it, that discusses (among other options) a number of low magic scenarios.Sargon the Kassadian said:I didn't mean a setting, I just meant a book devoted to discussing the issue, although I may be showing my ignorance in reference to third party "systems".
Not sure what you mean by third party "systems" -- maybe third party publications within d20? Several of those I mentioned were still Wizards of the Coast. And if you change systems, there's no third party at all anymore.