In this week's issue of the New Yorker Malcolm Gladwell reflects on plagarism. Starting from a case in which one of his articles was used as the basis for a stage play (without attribution), Gladwell uses the experience to explore ideas about fair use and copyright in other arenas, the article is an interesting read:
And this is the second problem with plagiarism. It is not merely extremist. It has also become disconnected from the broader question of what does and does not inhibit creativity. . . . The ethics of plagiarism have turned into the narcissism of small differences: because journalism cannot own up to its heavily derivative nature, it must enforce originality on the level of the sentence. [newyorker]
It's even written in a way that's accessible to people who aren't already deep in the trenches of the free culture movement!