In a recent audio podcast from Freakonomics called “Soul Possession” they talk to a Christian guy who in debating atheists would try to buy their soul, since they placed no value in it… and also to the guy who took him up on his offer.
It gets bogged down a bit in the middle as they run away with the idea a bit, but it’s an interesting discussion: is this a rhetorical move gone awry, or a useful discussion to have?