Ever needed to prove the cheque was in the post?

Hitachi has developed a tiny IC (integrated circuit) chip that can be embedded in paper to track parcels or prove the authenticity of a document, according to Forbes.

It measures just 0.15-x-0.15mm and is 7.5-micrometers thick. A micrometer is one-thousandth of a millimetre.

The chip is powered via electrical waves.