Re: Facebook simply would not exist today if not for Bletchley Park
> Or maybe some hardware from Leo Computers, International Computers and Tabulators, British Tabulating Machine Company, Marconi, Ferranti, or Acorn?
If memory serves, at least some of the vacuum tubes for some of the first post-WW2 British computers came directly from Bletchley Park; Colossus etc had been dismantled and the quartermaster at the local deppo was scratching his head about what to do with all this newfangled electronic equipment which didn't really seem to serve any purpose.
So on the one hand, at least one project got a boost from having "free" components, but at the same time, they also had to spend a lot of time reinventing the wheel, while the USA was free to take and apply the lessons which had been learnt during the war.
I'd also note that (for better or worse), Wikipedia states that Lyons built LEO after two of it's senior managers had flown over to the USA to look for some new business processes...
(I do actually own the "A Computer Called Leo" book, though it's been a long while since I read it!)
https://www.goodreads.com/book/show/1009975.A_Computer_Called_Leo