Courtesy of my father, a very good letter at the FT (in response to this piece on the top-secret room-sized computing machine named Colossus, invented by Tommy Flowers - site registration required):
A rebuild of Colossus can be seen by the public at The National Museum of Computing in Block H at Bletchley Park. Block H also happens to be the world’s first purpose-built computer centre and housed six working Colossi in the 1940s.
Before his death in 1998, Tommy Flowers took a great interest in the rebuild of Colossus, which began in 1994, and visited us to give his thoughts, reminiscences and moral support.
The rebuild took 14 years and in the Colossus Cipher Challenge two years ago it once again broke a Lorenz coded message in three hours and 40 minutes. However, a German using a laptop broke the code in just 47 seconds and won the challenge.
Head of Colossus Rebuild Team and Trustee of The National Museum of Computing at Bletchley Park