Tim Harford tells the fascinating stories of inventions, ideas and innovations which have helped create the economic world.
http://www.bbc.co.uk/programmes/p04b1g3c
Auctions
Are things only worth what people are willing to pay for them? Tim Harford explains why a method of buying and selling that originated in ancient times has endured to the present day, and is now underpinning the success of some of the internet's most powerful brands.