I fully support Seth Godin's rant:
"Professors should be spending their time devising pages or chapterettes or even entire chapters on topics that matter to them, then publishing them for free online. (it's part of their job, remember?) When you have a class to teach, assemble 100 of the best pieces, put them in a pdf or on a kindle or a website (or even in a looseleaf notebook) and there, you're done. You just saved your intro marketing class about $15,000. Every semester. Any professor of intro marketing who is assigning a basic old-school textbook is guilty of theft or laziness."