One of the few things I've taken away from Doctorow's work is the notion of Whuffie from Down and Out in the Magic Kingdom. I noodled on a brief implementation

One of the few things I've taken away from Doctorow's work is the notion of Whuffie from Down and Out in the Magic Kingdom. I noodled on a brief implementation on the Ethereum Blockchain, with a high level design of "anyone can issue and revoke to/from anyone else, and aggregate scoring is implemented by users", where my personal scoring system would have some kind of 3rd degree WoT evaluation, and normalize everyone's point-scores against the total quantity given by each of their point-givers". Ridiculously heavy and expensive to implement on Ethereum, but I'm sure some other backing storage could handle the weight and transaction volume. Probably worth writing up a whitepaper, as the cryptoderps say.