Japan making RFID-trackable cash

http://theregister.com/content/55/32061.html Japan's starting to add RFIDs to their 10000-yen (~$100) bills. Notes will come with Hitachi's 0.3mm "mew-chip" which responds to radio signals by sending out a 128-bit number. Each chip costs about 50 yen. The article says that each number _could_ be a serial number, but doesn't say that they know it is; the alternative would be something that indicated the production batch or whatever. The Reg's report sounds like it's based on what someone saw on a TV show, but also indicates they're starting production.