>What outfit they got you with these days? >MI5? SIS? - Respectively, the UK's >internal security agency, and the Secret >Intelligence Service, commonly (but >inaccurately) known as MI6.

In fact, MI5 is also an incorrect name. They're the Security Service. Shortening it has somewhat unfortunate connotations, though. MI5/6 were the liaison offices to military intelligence. The Security Service can trace their background all the way back to 1909.

And, just as an interesting thing, TUBE ALLOYS was in fact the first such program in the world.

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Stoke Mandeville, Esq & The Victorian Ballsmiths
"Nobody Want Verdigris-Covered Balls!"