[Rosie] Back in the Olde Dayes™ the phone exchanges in NYC were named, like those in London. One would dial two "letters" of the exchange name (in this case PE I believe though I haven't checked) then the digits 6-5000 giving the familiar (to a New Yorker) seven digit numbers. These days you have to dial four more digits because there are two area codes in Manhattan, the original "212" and a new one which we all think is "646", though no-one important would accept such a new-fangled invention and therefore anyone in a "646" area code is by definition not worth calling (pshaw). In point of fact, the Hotel Pennsylvania lost the 6-5000 number and only re-acquired it a few years ago amidst great media hoopla.
[Rosie] I forgot to add the startlingly uninteresting fact that all phone numbers must be preceeded by dialing a "1" when an area code is required in the USA. Which it always is when dialing anywhere in the five bouroughs of NYC. Even if you are in that area code when you dial. If you don't dial the "1", a recorded voice tells you to hang up and redial with the "1". This system was adopted at great expense for subscriber dialling convenience.
(Stevie) The names of London telephone exchanges used to be quite original, but have ceased to exist as such for about 40 yrs. Off the top of my head I can think of Waxlow, Pollards, Livingstone, Renown, Tudor, Museum, Bluebell, Vigilant, Speedwell. There are loads more in this vein that give you no idea of where they are. You don't need an area code to dial in London, but two four-figure numbers. There used to be a laundry near where I live whose number was Upper Warlingham 27. If it existed now it would be 01883 620027, not a London number, obviously. How boring it all is!
Well I was thinking things have got a little dusty recently, and looking through the MCiOS archives I note we haven't had a letter-writing game for a while. Not of the Mrs Trellis sort, but one where each player writes an entire letter. Examples of this genre include Letters to the editor and Wish you were here?. Of course, I'm always more in favour of things that haven't been tried before. At least, that's what I told the volleyball team last night.