Found in 2 comments on Hacker News
"A Computer Called LEO" - story of the first commercial computer, used to run Lyons teashops. Fascinating both in terms of computer history, and history in general, especially Lyons' attitude to perfectionism, to the extent of doing many things themselves, that these days would never survive an outsourcing purge.

http://www.amazon.co.uk/Computer-Called-LEO-Worlds-Office/dp...

"The Soul of a New Machine" by Tracy Kidder

Drags a bit in places, but is still interesting in a history type way. It's the story of Data General building a 32-bit minicomputer in a year in the 1970s.

http://www.amazon.co.uk/Soul-New-Machine-Tracy-Kidder/dp/031...

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