A lot of vise thoughts and advices have been given about mirroring and linking to your work.
What about frame-hijacking? (I.e. another site putting your pages in a frame of their site.) From a technical point of view this could be considered as a link. They tell the visitors browser to also get documents from your site. Logically and morally I feel this being a form of mirroring, though no physical copy of your work has been done. I'm not sure how a juridical department would define this behavior.
helps in many but not all cases.
I would like to think that it's not necessarilly your responsibility to actively protect your work, people (and companies) should respect your right to your work. But reality isn't always that nice and taking some simple precautions may discourage at least the more lame attempts.
Everything went worng, just as foreseen.