Nice to see that in addition to the Daily Mail the list of people monitoring this blog for ideas includes BBC Four, who evidently decided to tailor a programme to my exact specifications in a (successful, as it happens) bid to lure me in to watching it.
That programme was A Very British Map: The Ordnance Survey Story, which, as the name suggests, was largely about maps, and as an added bonus contained a short section about triangulation points, and mentioned in passing that some people bag them as a hobby.
A couple of mild criticisms: firstly for perpetuating the idea that paper maps are some sort of quaint anachronism that will eventually be consigned to the dustbin of history - while it's no doubt true that paper map sales have fallen, people will still want and need them for all sorts of good, practical reasons even while they're drooling over their wrist-mounted GPS podules at the same time.
Also, rather bizarrely, the woman doing the narration insisted on pronouncing the name of the organisation as "Ordinance Survey" throughout. Now the respective definitions of "ordnance" and "ordinance" do swim about a bit in my head, if I'm honest, but I do remember pretty reliably that the map guys make use of the word without the "i" in it.