Technical or formal discussions and mechanisms relating to copyright:

• Creative Commons (http://creativecommons.org/).
• Association Littéraire et Artistique Internationale (2007), “Memorandum on Creative Commons Licenses”, Columbia Journal of Law & the Arts, 29, 261-269,
• Lawrence Lessig's book “Free Culture”, 2004 (http://www.free-culture.cc/). All four of Lessig's books are available online under Creative Commons licences.
• Intellectual Property: A Balance (The British Library Manifesto) (http://www.bl.uk/news/pdf/ipmanifesto.pdf).
• Rosemary Bechler's “Unbounded Freedom” (http://www.counterpoint-online.org/cgi-bin/item.cgi?id=618). A PDF document and a podcast of a debate.
• Boldrin and Levine's “Against Intellectual Monopoly”, 2008 ( http://levine.sscnet.ucla.edu/general/intellectual/againstfinal.htm), which provides an economic argument for abolishing copyright (and patents). Interesting parallel between removing trade barriers and removing intellectual monopolies on the last two pages of Chapter 10.
• An explanation of how copyright works in New Zealand ( http://www.med.govt.nz/templates/Page____7290.aspx).

Passionate and entertaining arguments for greater freedom of distribution and sharing and reuse of creative works:

• Cory Doctorow's “Digital Rights Management” address to Microsoft's Research Group, June 17, 2004 (http://www.craphound.com/msftdrm.txt). See also Boing Boing and Craphound sites.
• Cory Doctorow's authors@google talk, May 21, 2007 (http://www.youtube.com/watch?v=xgXwmXpaH2Q).
• Professor Eric Faden's “A Fair(y) Use Tale” video using samples of Disney movies to explain Copyright and Fair Use (http://cyberlaw.stanford.edu/documentary-film-program/film/a-fair-y-use-tale).
• Eric Flint's “Salvos Against Big Brother” (http://baens-universe.com/columns/Salvos_Against_Big_Brother). An extended “rant” against the idea of trying to lock down digital content.
• Dr Michael Geist's Hart House lecture at the University of Toronto “Our Own Creative Land”, March 30, 2006 (http://individual.utoronto.ca/dtsang/hhlecture/index2.html).
• Richard Stallman's talk at the Computer Science Club at Waterloo “Copyright vs Community in the Age of Computer Networks”, July, 2007. Discussion about extending the freedoms provided by free software to other creative works. (http://www.csclub.uwaterloo.ca/media/Copyright)
• Alternative Freedom (documentary; I've only seen the trailer so far) (http://alternativefreedom.org/).
• Steal This Film. (http://www.stelathisfilm.com/).
• Good Copy, Bad Copy: A documentary about the current state of copyright and culture. (http://www.goodcopybadcopy.net/).
• Eben Moglen's Keynote Address at the Plone Conference, “Software and Community in the Early 21st Century”, October 27, 2006(http://www.archive.org/details/eben-moglen-oct-2006).
• Eben Moglen's annual lecture of The Scottish Society of Computers and Law in Edinburgh, 26th June 2007
  (video: http://www.archive.org/details/EbenMoglenLectureEdinburghJune2007StreamingVideo384kbits)
  (audio: http://www.archive.org/details/EbenMoglenLectureEdinburghJune2007)
  (text: http://www.archive.org/details/EbenMoglenLectureEdinburghJune2007text)
• Eben Moglen's "The dotCommunist Manifesto" http://emoglen.law.columbia.edu/publications/dcm.html.
• Eben Moglen's "Free Software, Free Culture: After the dotCommunist Manifesto" http://opencultures.t0.or.at/oc/participants/moglen/video.ram
• Lawrence Lessig's “Open Code and Open Societies” in “Perspectives on Free and Open Source Software” (http://mitpress.mit.edu/books/chapters/0262562278.pdf).
• Lawrence Lessig's Last Lecture (on copyright) ( http://www.opensourcecinema.org/lessigfinal). Includes a good simple summary of the "highlights" of copyright history.
• Keith Aoki, James Boyle, and Jennifer Jenkins' comic book “Tales from the Public Domain: Bound by Law?” (http://www.law.duke.edu/cspd/comics/).
• Kevin Kelly's Better Than Free. With some ideas on how to make money when copies are free.
• Johanna Blakley's TED talk: Lessons from fashion's free culture with some interesting points about industries that do NOT have IP control.

Some dissenting voices (or at least some warnings about the risks involved in using Creative Commons licences) ...

• Virginia Morrison's "Creative Commons - The Fine Print" (http://www.watchthisspace.org.nz/article/creative-commons---the-fine-print/25337).
• The Association Littéraire et Artistique Internationale's "Memorandum on Creative Commons Licences" (http://www.alai-usa.org/Memo%20Creative%20Com%20Licences%20jg%20rev%2022%20jan.doc).

Other stuff, some of which has a more tenuous relationship to copyright, but is still related to the “free culture”, individual-participation movement:

• The O'Reilly press release announcing their use of Creative Commons licences (http://press.oreilly.com/pub/pr/1042).
• The Global Text project (http://globaltext.org/index.html).
• The Open Content Alliance (http://www.opencontentalliance.org/).
• Google Book Search (http://books.google.com/).
• The One Laptop Per Child Project (http://www.laptop.org/).
• Project Gutenberg (http://www.gutenberg.org/wiki/Main_Page).