Vainglorious Vicissitudes

Textbooks cost so much because of the limited market. The CD-ROM probably doesn't add mre than $3 to the cost of the book, though royalties for the content on it might. But because nobody buys that book, the publisher has to recoup the one-time expenses for the production run on a much smaller print run. Those one-time expenses are sometimes significant - color illustrations and fancy typesetting aren't cheap, either.