Tango Icons

http://tango.freedesktop.org

http://lists.freedesktop.org/archives/tango-artists/2007-May/001317.html

А что там?

>>The color palette is public domain. The icon theme is also available as public domain since the 0.8.90 release. While you are not obligated to, we would appreciate if you credit the project if you chose to use the icon theme or derivative artwork in your project by linking to our website. This will help to strengthen the awareness of the style guidelines. Thank you.