A new device can track an individual, shoot an aroma directly at their nose, and leave the person next to them completely unaffected.
The air cannon was developed by Yasuyuki Yanagi and his colleagues at the Advanced Telecommunications Research Institute in Kyoto, Japan, as a technique for directing evocative smells to people exploring virtual-reality environments. The driver of a car simulator, for example, might sniff petrol as they drive into a filling station or freshly cut grass as they pass a sports field.
But marketing specialists could seize on the air cannon as a way of tempting shoppers by wafting the scent of the latest perfume or an expensive blend of coffee in their direction - perhaps in conjunction with in-store video adverts. Or high street poster sites could fire ad-related odours at you as you wander past.