A thought on the current discussion on the economics of free software:
In answering the "why people write free software," some are comparing it to art, some to science. It occured to me that maybe one reason it's hard to peg is because nothing that came before can compare. It's its own new creature. In the future perhaps someone will try to come up with a reason for a new endeavor and say "it's like writing free software."

No energy to flesh this out for a post. If you read it feel free to expand...