Until now I licensed the contents on this website under the "Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported" license. This license does not permit commercial use, so that I just changed the license of the website contents - including a copyrights statement in every footer and the feeds - to "Creative Commons Attribution-ShareAlike 3.0 Unported".
This license - roughly - only enforces you to share modified ot republished contents under a similar or equal license, include a copyright statement and reference the original author. For details you might want to read the full license ;).
It may happen, that I license some pages under different licenses, so please pay attention to the license in the footer if you want to republish any contents.