Difference Engine with a Difference.

BBC News reports:

The blueprint for a tiny, ultra-robust mechanical computer has been outlined by US researchers.

The energy-efficient nano computer is inspired by ideas about computing first put forward nearly 200 years ago.

Basically, the designers are looking to Charles Babbage’s difference engine as a model:

[The] "difference engine" . . . consisted of more than 25,000 individual levers, ratchets and cogs and weighed more than 13 tonnes.

Although none of his designs were ever finished, recent reconstructions by London’s Science Museum show they were capable of carrying out complex calculations.

The US team’s proposal owes a debt to these early concepts.

"It’s inspired by Babbage’s ideas but these days we can scale it down," Professor Blick told the BBC News website.

"Now, we are able to process devices on the nano scale."

Heather McDougal of Cabinet of Wonders sees this as science fiction coming to life, comparing the development to technologies envisioned in  The Diamond Age, by Neal Stephenson, while her commenters cite Stephenson’s Cryptonomicon and The Difference Engine by Gibson and Sterling.