During a routine credit card transaction recently in the UK the sales person took the card, checked the expiry date and tutted “It’s just about still valid” – it is due to be replaced in 03/07. A gentle example of how people treat things with expiry dates and times, whether credit cards, parking meters, foodstuff, differently the closer it comes to being due. Another common example, particularly amongst the male bachelor of the species is sniffing milk before pouring – trusting the sense of smell over the date on the side of the packet.

As we continue to learn how to control what happens at the nano + bacterial level there is greater scope to communicate current expiry status: ID cards that visibly or olfactorily depreciate closer to that time; money that feels different when you’re down to your last ten Euro note – prompting a visit to the nearest ATM; containers that tell you much more about the condition of what is held inside.