I have been wondering recently what the effect of duplicate content would be if you are the author of the content.
Lets say for example, you contribute an article to a popular website and you have your rel=author in place on the article. But then lets say you also want to include that article on your own site, or a version of it. You also include the rel=author in that page.
1) use a canonical tag to the original
2) noindex the duplicated article
3) Use robots to prevent the page from being crawled
4) Not risk using the article (even though its your own and has rel=author in) on another site
I would be very interested to hear your thoughts.