[contingencies]

Part of the issue here is that to describe such entities there needs to be a means of standardization.

We saw 'carbon credits' devolve in to specific-exchange linked, unique entities that were not interchangeable across borders. That made meaningfully adopting them as environmental units to stake a claim for the value of environment in the present-era systems very difficult. That situation perhaps evolved partly because nobody could otherwise agree on an appropriate level of auditing, and partly because .. well .. established interests. (Without nationalizing and centralizing these things, their potential for decentralized issue versus centralized government fiat issue poses a threat to both sovereign currencies worldwide and the vast profits of connected financial services industries.)

Historically, part of the control effected against change within the financial environment is that SIX in Switzerland on behalf of the ISO has controlled the major ISO4217 global currency and commodity registry, locking out innovation and essentially refusing to issue new codes. People have been avoiding that gridlock by making up unofficial codes like 'BTC' for Bitcoin and such. I recently proposed registry of these values via the IETF at https://datatracker.ietf.org/doc/draft-stanish-x-iso4217-a3/ however it's expired pending a new release at the moment (adding Litecoin, etc.)

(On the off chance anyone's hitting OHM2013 later this month in Holland, I'm planning to give a talk there on this subject and related matters at the intersection of politics, finance and technology.)