My brother attended a service academy, and their books were just "issued" to them for free. At the end of the year, tons of students threw theirs out. My brother snatched some of the valuable ones up, sold them on amazon, and bought himself a flatscreen TV and a PS3. Another friend of mine collected up all the old edition books at our school, and then went and sold them back at other university bookstores in the area that hadn't switched editions or were offering more money.smuphil
I work at a school and at the end of the year there are just stacks of books the kids leave out to be thrown out.
I bought a $300 Sonos speaker with the sales of them this year.