My dad used to be dept chair at the college where he worked. Because of his title, textbook publishers would send him copies of their books for consideration. He would give them to me and I would sell them on half.com.
He was also able to order the answer books for my calculus textbook. I could do all the practice problems and look up the answers (not just the odd # questions which were in the back of the student book). At the end of the semester, I gave the answer book to the chair of the math dept to keep in the student math lab.
Also, one day in my physics class, some textbook sales reps came to demo this new RF remote with numbered buttons like a TV remote. Each student in class would get one. Their sales pitch was that it would allow our teacher to put a daily quiz up on the projector screen, and each student would use the remote to submit their answer, and then his TA wouldn't have to grade 150 quizzes. Also it would track attendance (which I thought should be optional for college classes). Students were expected to pay for their own remote, and I think there was a license fee per semester. Yuck.