And then there are resources like cramster.com, which provide (often for a fee) complete, often correct, solutions to all the textbook's problems.
All this reinforces an old question: are we really teaching what ought to be taught? Why should we be teaching—at least to the extent common in so many courses—the "subhuman" pencil-pushing symbolic manipulation skills that seem to saturate the content?
One answer: A course that does otherwise—that concentrates upon actual intellectual content (motivation by means of real-world situations of actual interest to students and other humans; understanding, and by that I do not necessarily mean rigor; and genuine applications rather than the made-up pseudo-applications that permeate all too many courses)—can readily turn out to be much too sophisticated for many students. Or at least such a course requires a completely new approach to learning by students accustomed to the traditional approach of mindlessly calculating.
We're trapped, in a way!