Amazon Algorithm Price War Leads to $23.6-Million-Dollar Book Listing

What do you usually expect to pay for a book on Amazon? Perhaps $7-$10, if you're scouting for a paperback? Around $20 or so if you're looking to score a hardcover? Maybe $1,000-$1,500 if you're trying to hunt down that elusive, rare edition of "Teaching With Calvin and Hobbes?"