I have installed tracer by http://www.tynt.com on my blog at http://www.mentalmeals.com and am using it to see if others are copying my content without giving me credit. It also sends links back to my original post automatically.
The tynt.com website does not have WP instructions for install, but I found them on http://sidekickblog.com/track-whats-been-copied-from-your-blog-83.htm
I will install it on all of my blogs and website pages.