We've all had one of those scam e-mails asking us to send the writer a few hundred dollars, with the promise of a huge return on investment a little later. They usually begin with something like "Dear esteemed friend", and end with bank account details that the unwary can send their money to.

This account of the Internet cafés of Lagos in Nigeria gives a fascinating insight into where these fraud e-mails come from. Not from organised crime gangs, but from dozens of young Nigerians with the patience of gold prospectors and the chutzpah of the door-to-door salesman.

"I saw a letter being written from the 'Chairman of the National Office for Petroleum Resources' by a man who was chairman of nothing. There were other letters, from the heirs of one fictional magnate, from the widow of an oil baron. Enterprising samples of narrative fiction. Lagos is a city full of writers."