Coen Jacobs

Makes it easy to display a link to the Creative Commons license you desire in posts and pages.
It adds the following features:
<ul>
<li>Options to add a link to your Creative Commons license under all posts</li>
</ul>
Read more about this plugin on the <a href="http://coenjacobs.net/wordpress/plugins/creative-commons-suite" rel="nofollow ugc">Creative Commons Suite plugin</a> page.

Creative Commons Suite

Makes it easy to display a link to the Creative Commons license you desire in posts and pages.

CodeAndReload

This plugin provides the ability to tag media in the media library as having a Creative Commons (CC) license. 
The license shows up on the attachment page and is optimized for search engines (SEO) using RDFa metadata. 
It optionally extends the search form to allow searches for CC-tagged media. It can display a text link 
to the license, an image link to the license, or both.
<h3>Support</h3>
Technical support for this plugin will be provided via the WordPress plugin forum. Additional support may be 
available at <a href="http://www.codeandreload.com/wp-plugins/creative-commons-tagger/" title="Creative Commons Media
Tagger at Code and Reload">plugin’s homepage</a>.

Creative Commons Media Tagger

Allows tagging of media as having a Creative Commons license. License info shows as link and/or image and is searchable. Search engine optimized.

Creative Commons Suite vs Creative Commons Media Tagger