I wrote the following comment about GettingPaidForContent (essentially you can't)
But maybe this can be automated and made an integral part of the content. I wonder if something as simple as a MicroFormat for some kind of "live" content would work.
For instance, I put out some information as a chunk of XML which is designed to be copied and flowed through syndication feeds etc. and, naturally, includes a URI which links back to my server and which my server uniquely understands.
Then there could be re-use cases which would involve the viewer or aggregator "phoning-home", not as a method of DRM enforcement, but because my server would provide updates of, or contextual information about, the content. A genuinely integral part of the product.
For example, maybe you can give away essays, but sell a live connection to a server which has information about how many people are bookmarking or reading the essay. Before the reader wastes his / her time reading it, she can get a notion of how popular it is.
The important point is that the content creator must own the pings or "gestures" that the content engenders. Not as a way of restricting its distribution, but as something which increases the content producer's own ongoing value to the consumer.
(Heh! Maybe you could call this "Data Alongside" as opposed to "Data Inside" :-)