How often do you appropriate bits from books, movies, comics, and other sources as a player or GM? Do you like to steal names or flavor or go more whole-hog? Is there a difference between stealing for background and stealing for in-game plot?
I may borrow specifically if the game is meant to be more humorous, while in more serious games I only use themes, attitudes and the like. I suppose this is because I see using such bits as somehow being disruptive to the flow or atmosphere of the game (assuming it’s a bit that isn’t from the same fictional universe), and that tends to be less of an issue in a game that’s supposed to be funny.
In any case, it’s something I do very rarely as a player in either sort of game. I find fiction to be a source of inspiration, but somehow it seems like a copout to simply steal things from another source and incorporate them into something that’s supposed to be my creation.
As a GM, I suppose it would come down to how well the fictional person or item fit in with the rest of the game, but I’d still be inclined not to do it (or to allow a player to do it). The exceptions would be those games where I’m purposely running in a borrowed setting (or a mashup of two or more settings).