I have reported before about what a rip-off textbooks are. The obvious solution is to teach without one, but today's students insist on them. But help seems to appear on the horizon, in the from of Flat World Knowledge, a commercial publisher that sells hard copies, at lower prices than the competition, and offer the PDF files for free. This is quite an interesting commercial strategy, which has also been adopted by some open access journals that provide print-on-demand services at some cost but otherwise keep the journal free. In economics, Theoretical Economics comes to mind.
Hattip: Against Monopoly