I set up a book exchange like this outside my office door when I used to work. Only we didn't have a requirement about no sh*t books. I'm pretty sure we read a lot of sh*t books! It was fun, it got everyone reading.
"Book collecting is an obsession, an occupation, a disease, an addiction, a fascination, an absurdity, a fate. it is not a hobby. Those who do it must do it. Those who do not do it, think of it as a cousin of stamp collecting, a sister of the trophy cabinet, bastard of a sound bank account and a weak mind."
— Jeanette Winterson