[II2II]

When editions changed and problems were assigned from the books, most of the profs at my university would gladly provide copies of the updated questions. I even had a course where students would bring in photocopies of the prof's textbook to class, and he was still willing to pay a Knuth-esque stipend to students who found errors.

I had one that was the exact opposite, even going as far as violating the university policy by charging for quizzes. The administration refused to do anything about that one ...