In Jon Ippolito's talk Hacking CopyRight for Fun and Profit, he lays the groundwork for sharing as a legal framework using licensing, specifically Creative Commons licenses. The basic thrust behind the talk is that basic copyright, while useful, is outdated in the age of the internet, and needs to be supplemented with legal protection that promotes rather than inhibits re-use, re-mix, collaboration, and sharing. He promotes Creative Commons licenses as this solution, licenses that retain copyright while granting permission for certain forms of re-use.
Two things strike me about this talk and the approach to the discussion of copyright. First of all, Creative Commons (CC) licenses address the needs of creators who want to share their work for purposes of viral collaboration and networking. It lifts the haze of legal ambiguity from works that bear no copyright symbol (which are unnecessary anyway), and clearly states the legal rights of a user who may wish to reference or re-use the work, depending on the license. This may not seem initially like it addresses a critical need, however, Ippolito makes the case that creative re-use is a emergent cultural norm that not only closely matches the ethos of the internet, but of the larger academic and artistic community. In the same way that copyright protects authors from infringement, Creative Commons licenses protect authors while allowing free sharing of information, and potential free publicity (via resultant derivations) for the work. This is different from the types of broadly naive arguments made by some free-sharing culture types who ignore copyright altogether and promote fraudulent sharing of music and other types of file-sharing.
Secondly it promotes a culture of informed legal protection coupled with openness, that gives authors a mechanism for using and creating derivative works. In many cases they are already doing this. The examples given are HTML and related code-sharing. The focus is not on copyright infringement (illegal copying by consumers), but of granting rights by authors to share information. Promoting the informed legally protected culture of sharing empowers individuals to seek and use Creative Commons (CC) works. This approach leverages the power of sharing on the Internet for creative authors without fear of legal prosecution.
Artists can use Creative Commons licenses to metaphorically suggest implicit interactivity or generative nature of their work. One example would be Steal This Book by Abbie Hoffman (1971, Pirate Editions). http://www.amazon.com/gp/product/images/B0000CPGXF/sr=8-2/qid=1263928108/ref=dp_image_0?ie=UTF8&n=283155&s=books&qid=1263928108&sr=8-2