Copyright is important. Don't get me wrong. But I am so damn annoyed with the people who put that two-line javascript on their page to prevent people from right clicking (even if it is just over images).
LISTEN TO ME I am not trying to steal your images!!! And Even if I was, a stupid little java script alert wouldn't stop me. I, in fact, like to use my right click to copy and paste things as well as to go back and forward within the browser. So settle down and cut that crap out.