Can Programmable Money Be Used for Good or Evil?

Programmable coins can be programmed to behave in certain ways. In the case of china, a imagine a coin, adigital currency, where some portion of it could only be used for a specific purpose. If you can limit a coin to being spent on the subway, essentially what you're doing there is preventing coin from being spent anywhere else. And with things like programmable money, that that gets pretty scary pretty quickly.