>Copyrights are supposed to be issued for intangible ideas.
Everything you might describe as an intellectual property does not neatly fall into categories like that, especially not on the grounds of tangible/intangible. It's not simple. Sorry.
Maybe the 'machine or transformation' test confuses this area - but it applies to a patent application for a process. The hacker's way round that is to claim computer-implemented inventions as part of a computer system (the tangible device) which implements the algorithm.
Most relevant to your comment: Copyrights are *always* for the physical embodiment of an idea. A work (whether you call it art or not) is essential to the notion of copyright. The Lion King copies its story from Hamlet but it would not infringe a copyright -- were there one in place -- because it is not an animated film which implements the text of Hamlet (you can see that they share the intangible story idea of a prince crushed by the guilt of his father's death, even though it was caused by his evil uncle, fleeing to escape that guilt but ultimately returning to avenge the actions of his uncle). In contrast, a copy of Metallica's 'Master of Puppets' album is a likeness of the original recording which directly derives from that source and wouldn't be valuable unless it was a tangible representation of that original sound recording.