@Moon Man, if only there was a public ledger with no central authority that could be used to set up such a system. Preferably using some kind of universal software everyone has the source of and universal access to, that could enforce it like contracts. That would be pretty smart.
@Moon what doesn't?
@Moon oh I missed "free/free-ish" somehow. Everything will at least require the resources to run the hardware that makes it possible so free is impossible, methinks you can't go lower than the costs of a sensible contract on a sensible blockchain, best you could do is have volunteers or publicly funded organisations that pay it/run it for people to make it "free".