High fantasy and gunpowder, with a twist: How would such a world look like?

[Don]

Has anyone made up any d20(c)(r)(tm) rules for gunpowder and primitive tech in their games (feats, skills, additional combat rules, etc)?

I've just been playing Arcanum on my computer for the past week and I think a half-magic, half-early industrial tech world would be fun to roleplay in.