Electronic dust that can track and authenticate anything from banknotes to human beings may soon be more than science fiction if Hitachi's latest tiny RFID chip finds a commercial application.

The µ-Chip, which has 128 bits of ROM capable of storing a number with up to 38 digits, measures just 0.15 mm x 0.15 mm x 0.0075 mm - you can (just) see several of them in the photograph alongside much larger grains of sugar.

One time deal

Although far less sophisticated than the IC chips found in many modern smartcards and electronic devices, the µ-Chip has great potential by virtue of its diminutive size.

Its memory can be written to only once - at the time of manufacture - making it impossible to change and, thus, suitable for authenticating the origin of anything of value.

Single chips could be embedded in paper money or gift vouchers, which would then be vulnerable only to forgers possessing Hitachi's chip-fabrication technology; an unlikely situation.

Other scenarios could see the chips sprinkled like dust on the clothing of anyone being monitored in a secure area - although this raises inevitable privacy fears - or embedded in product packaging to aid stock control.