Mathilde Epron, 32, said she had bought a Kit Kat chocolate bar at her local supermarket but initially threw the wrapper in the bin, telling herself that "it's only others who win.

In addition to selling green tea leaves, tea merchants have distilled the brew's essence and added it to gum, soft drinks and skin creams - even, in Asia, to Kit Kat candy bars.

There were a lot of factors that contributed to the success of the Kit Kat campaign, but its success wasn't isolated from our other online campaigning.