The idea of "leadership feats" kind of intrigues me. Not got anything particular in mind, but perhaps they could effect tolerance for abusive NPC uses.
No, there's a specific feat called Leadership, and it's broken as hell. It basically lets you play an additional party member, though at most it can be up to 2 levels lower than your own, and whether you or the GM actually controls it is a matter of houseruling. I'm guessing Roger prefers to treat them as semi-independent NPCs, though.
Considering pre-WotC D&D allowed you to gain henchmen as defacto lower level PCs plus however many hirelings you could afford plus what ever your class' name level followers, if any, were, the feat is less broken since you have choose it to gain followers and a cohort.