steve toltz' very excellent "fraction of the whole" contains the alarming observation that while people forge paintings, they never forge novels.
in jazz, a lot of us use the "Real Book" which is a huhe tome with the words , chords and melodies of lots of "standards" (songs from the classic era's of jazz from dixie to swing to beop and cool and back again) - far as I know, the "real book" is a massive breach of copyright - luckily, nowadays, sheet music is not the Evil EMpire that it used to be when a) there wasn't P2P file sharing MP3 recordings to blame and b) people used to play the latest hits themsevlves on the piano in the "drawing room" - so slack has the copyright protection on sheet music become that people can get the "Fake Book" whcih is an "illegal" photocopy of the real book!
[bill bruford, in his amusing and interesting autobiography, cites some muso-socio-journalist as wisely pointing out that the "value" in music moved from medieval times being vested in the player, through vitorial times being vested in sheet music, to the 20th century being locked up in frozen recordings - a recent article in the guardian talked about new models of direct composer/player to audence via the web, which may be a final reversion to the oldest model, but usng the newest tech, which is a fine thing in my opinion)
in the world of software, you get things called "counterfeit" copies of Windows - but more interestingly, you get reverse engineered programmes...which actually involve some skil and are, basically, legal...
so why is the same set of law applicable to all these walks of life? weird.