Here I go getting myself into trouble by being the devil's advocate (so to speak). It seems to me (though I may be wrong) that it's unlikely that anyone here will take any legal action against a person steals a piece of work or take action against a site who allows it to be displayed. Without going into all the details (that have been argued before), there is proof of damages, different countries involved, etc. And considering the difficulty that an entity as powerful as the recording industry has had trying to stop pirating of songs (which IS a loss of revenue), I think most any of you (I'd say, "us" 'cept I have nothing steal-worthy...hehe) would be wasting your time. So, to keep this small, it seems the best approach is to prevent the theft (NOT run around all the sites of the world writing letter to get them taken off after-the-fact). However, IF it can be displayed on the screen, it can be captured. SO.... though it detracts from the beauty of the art, why not put big semi-transparent lettering across the middle of your work that says, in some appropriate wording, that the work belongs to you? I'd give an example but I'm at work (shhhhhh....). (OK, I'm done, now start ripping me up....sigh...)