Trust Is Risk
MaxFlow non Sybil-attackable decentralized monetary trust using 1-of-2 multisig
Each user's coins are stored in 1-of-2 multisigs, shared with trusted parties. If the trusted party uses these coins, the user's trust towards the party is (tautologically) depleted. This allows for quantifiable monetary direct and indirect trust from one party to another. The indirect trust is proven to be the maximum flow from the first party to the second. It is also proven that it is possible for a client to engage in financial activity with an unknown store without increasing her risk towards the store. Furthermore, it is proven that the generic Sybil attack does not provide an attacker with any benefit.