A fascinating half-hour broadcast on Radio 4 yesterday really grabbed my attention - The Smell of Money looks at the growing prevalence of the cashless society, and its implications for modern economies. A lovely accompanying article on the impact of forged money can be found here.

As a short extension activity that could follow on from using these resources, students could consider the following question (one of my favourite mock interview questions):

Suppose that aliens on Mars have found a way of forging our money so that it is completely indistinguishable from ‘official’ currency. They then come to Earth on a shopping spree, and take their purchased goods back with them to Mars. Who pays the cost of the shopping spree?