Which mentioned NPCs have you ran with?

[Glyfair]

I was noting the lack of information on Zelligar the Unknown and Roghan the Fearless in the module B1 In Search of the Unknown. Almost nothing is known of them, and you can easily run with them and base a whole campaign backstory on what happened to them. The AD&D DMG was full of such references, especially in the artifact section.

Which throwaway mentions of characters have you taken and ran with in your campaign?

 

[Whizbang Dustyboots]

I've turned the mention of the Fables of Burdock in the 1E DMG artifacts section into the main conduit for background lore in my campaign. Burdock wrote so many stories, few people have all the volumes, meaning there's always the ability to drop in yet another story that folks haven't heard before, but that the NPCs might know.