I personally like Scalzi's and Stross's stance best. I think that their rules are what all authors should live by. They know fanfiction is a sign that their work is moving people and that fighting internets is a waste of time and effort. They just want to make sure he won't suffer financially as they make their living from writing. No talk about raping children or something (seriously, if you did to your children what you do to your characters...)
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