Greg Costikyan, an award-winning games designer (he's the man behind Toon and others) who makes his living off of copyright, has written a brilliant editorial on the nature of intellectual property today.
In general, when the RIAA complains about file-sharing, the refrain is that "artists" are being ripped off. I agree, 100%. Artists are indeed being ripped off–by the members of the RIAA. Anyone with more than a cursory understanding of business practices in the recorded music industry understands that the labels have refined the business of screwing recording arstists to a very fine art. With rare exception, musicians never see a dime beyond their initial advance–nor will they if the RIAA succeeds in its effort to suppress file trading. Realistically, this is not about defending artists. It's about defending the labels.
Recently, I went to a movie, and was subjected to a spot from some film industry organization, I do not remember which, that featured a fellow who is a set maker for the movies. He spouted some nostrum about how people who 'steal' movies were screwing him, not the studios. I was not impressed. He's a member of a craft union in Hollywood, and receives union scale when he works; I very much doubt he gets residuals, or any kind or royalty on the films that get made. His income is not affected one whit if the studios lose income through 'piracy'. To be sure, if fewer movies get made because piracy affects Hollywood's revenues as whole, he may be affected–but this is at best a red herring. It's the suits who'll suffer first.