jyosim writes: "Some see it as the latest ploy by textbook publishers to kill the used book market: 'access codes' for online supplements for course work. In some cases professors require students to purchase these codes in order to even see the required homework. One U. of Maine's student's struggle to find a reasonably priced textbook demonstrates the limits the new publisher practices put on students, but some argue that ultimately the era of digital course materials will be better for student learning." Link to Original Source
"A complex system that works is invariably found to have evolved from a simple
system that worked."
-- John Gall, _Systemantics_