The UK's early and pioneering contributions to world computing are being kept alive not by government grants or National Lottery hand-outs but by a small band of volunteers who give up much of their time to get historic machines back into live operation and public display.
The BCS Computer Conservation Society has largely been responsible for rebuilding the code-breaking Colossus from the Second World War. The machine, now on display at Bletchley Park, was put together mainly from a few preserved rough drawings and people's memories, because the machine was so secret that all records were destroyed after the war.
The first computer to run a program stored in its own memory, developed at Manchester University in 1948, was also rebuilt from notebooks, photographs and personal recollections. This machine is now at Manchester Museum of Science and Industry.
A Ferranti Pegasus computer, which is due to go on display at London's Science Museum in November as a working exhibit, has been rebuilt by society members - who will also take turns to run the computer and explain it to visitors.
The Ace computer, based on the designs of Alan Turing, a mathematician and early advanced thinker about computing, will be part of the Making of the Modern World exhibition at the Science Museum.
Work is continuing on the Bombe, an early decoding machine at Bletchley Park.
"Britain has a lot to be proud of from that early period," says Brian Oakley, who has just completed a spell as chairman of the Computer Conservation Society.
"It is really important to show young people and other visitors that Britain played a major part in the development of computing. It is also important to preserve the heritage of the machines, if only via emulators."
The society is now also turning its attention to old software.
"There is a very distinguished British history in operating systems in particular," Oakley says. "Paging, virtual memory and other concepts were developed here."
Most of the work is done with no formal funding, although the Bombe project - expected to cost £250,000 - has found industry support, especially from Nortel, which also has got its retired staff club to give practical help.
Oakley also pays tribute to the Science Museum, which provides premises for some of the work, and encouragement through Doron Swade, who is responsible for all the museum's collections.
But his greatest tribute is reserved for the volunteers, "We are absolutely dependent on members," he says.