Joshua Gans alerts me to a minor brouhaha over Neil Gaiman (a fantasy and science fiction writer) charging a library $45,000 to give a talk. Mr Gaiman apparently understands the concept of opportunity cost (principles number 2 in my favorite textbook). Here is how he explains his fees at his website. Q. How can I get Neil Gaiman to make an appearance at my school/convention/event?A. Contact Lisa