"Drinks or info chummer, both cost. One costs cred and the other costs favors. Too much of the former will give you a killer hangover, and too much of the latter might just kill you altogether."
A bartender contact/info broker for the Shadowrun rpg setting, can be easily adapted to any cyberpunk or other high tech campaign.
You've probebly heard of the real Thomas Hopkins, Witchfinder-General, who hunted down and hanged suspected "witches". What if there was a world/realm where magic was normal, and it was the non-witches and non-wizards who were hunted down and hanged as inferior beings?