Britain's most spectacular commemoratives, No39: 1999 Inventors' Tale 63p

In the first of the Millennium series, the highest value took as its subject the development of computers, commemorating in particular the work of Alan Turing. 

A cross-section of a human head has various pieces of computing hardware laid out as if inside a machine, reminding us that the brain itself is a very complex computer, which it had to be to invent the computer!

Design: Sir Eduardo Paolozzi.

Printing: offset lithography by De La Rue.