The photograph on the left shows salt-like Hitachi RFID mu-chips on a fingertip, while the right shows their new RFID "powder" chips, 64 times smaller, next to a human hair. RFID is scary enough as is, but this is getting close to "smart dust", and I can only imagine how intelligence services must be drooling.
The excellent site Pink Tentacle has the details:
By relying on semiconductor miniaturization technology and using electron beams to write data on the chip substrates, Hitachi was able to create RFID chips 64 times smaller than their currently available 0.4 x 0.4 mm mu-chips. Like mu-chips, which have been used as an anti-counterfeit measure in admission tickets, the new chips have a 128-bit ROM for storing a unique 38-digit ID number.
The new chips are also 9 times smaller than the prototype chips Hitachi unveiled last year, which measure 0.15 x 0.15 mm.
At 5 microns thick, the RFID chips can more easily be embedded in sheets of paper, meaning they can be used in paper currency, gift certificates and identification. But since existing tags are already small enough to embed in paper, it leads one to wonder what new applications the developers have in mind.