My latest RPG release… for Pathfinder

Yes, I'm aware that this is not an old school RPG, but it's a damn fine system (objectively speaking, of course).

Five Families: Criminal Organizations for Every Campaign World is a little .pdf I did for Adamant Entertainment. Besides the five detailed organizations, you get rules to create your own and delineate their powers and influence. If you're in the market for an underworld populated by insidious groups besides Ye Olde Thieves' Guild, you should check it out. Works pretty well with D&D 3.5, too.