Yeah, here's a little known fact about IMVU's economy: Most products allow derivation, which gives content creators the ability to tweak/remix/reskin the product and publish the changes back to the catalog. Pick a markup for the remixed version and presto, everyone in the derivation chain gets paid their respective markups for every sale. There are only a handful of root nodes; nearly every product is a derivation of another product.
Ted Nelson had a project called Xanadu, that amongst many other things kept track of partial contributions to derivative creations.
If you came up with this independently you may want to look into to the Xanadu project for more inspiration along these lines, it is definitely very interesting reading.
Ahh yes, I'm familiar (though not familiar enough) with project Xanadu. The concept of keeping track of derivations is fairly common; far less common is the idea of derivation for the express purpose of indicating participation in the value chain and thus participation in the compensation.
Beyond the product side of the economy, which is fascinating to me in it's own right (for some of the reasons you mentioned), the service economy around room rental, sales positions for goods and modeling services are just as interesting as well (let alone the complications of exchange rate, credit inflation, and other economic concerns).
