My ten year old is a Scratch addict. (http://scratch.mit.edu/) He could spend all day taking apart other kids' programs, remixing them, re-uploading them, leaving comments, reading comments, and playing silly, amateur games and animations online. Everything on this acclaimed, M.I.T-hosted, Web 2.0 Mecca is free for the taking. You can't steal on Scratch because nothing belongs to anybody; it all belongs to everybody.
For example, my son downloads a neat little animation that he finds, opens up the code, adds his own avatar or art to the project, recompiles it and loads it back onto the site as a different version -- a remix. It is an honor to be remixed, because it means that others ran your project and enjoyed it enough to add their own code. And it is considered in good taste to remix others -- a way of showing respect.
The Scratch admins at M.I.T. take this remix activity so seriously that they have a beautiful graphical display of the family trees of projects: http://scratch.mit.edu/projects/dragonfireB/1151932/mods You can see how lines fan out and split like family trees as the project evolves. Projects are ranked by the number of remixes they have engendered and authors with high remix statistics are esteemed.
Participants can review, rate and comment on projects, just as they do on blogs or commerical sites like Amazon. But the Scratchies have found a new way to use this feature: participatory fiction. They write stories comment by comment. While there is no rule saying that this is the wrong way to use the comment feature, who would think of using it that way? Kids would. So if there ever was an implied rule that you only write comments in the comment box, that rule is now thoroughly broken.