A very nice, legally-protected arena for sharing creative works and data, created by a Harvard lawyer, Lawrence Lessig. It is distinct from software licenses in that it is intended for creative content, not really code.
Personally, I see the CreativeCommons group of licenses for the content made by users within domains made possible by FreeSoftware and the GNU Project.
See http://creativecommons.org/
Also see OpenContent, OpenArchivesInitiative, PublicLibraryOfScience, and BudapestOpenAccessInitiative, GnuGeneralPublicLicense.