For example, you have a website that is made up of mostly your own original text, some explicitly commercial (and therefore limited) licensed photos, and then you go and add blocks of text to the site in various places that are adjacent to the other content, and that text was licensed under the Creative Commons license (http://creativecommons.org/licenses/by-sa/3.0/legalcode). Is your whole site, or any portion of the site that was not originally taken from a Creative Commons licensed source now free for the taking? Or is it only the case that any modifications to the text that you used are free to be used by others? Does the entire site constitute a derivative work? Where are the lines drawn?