Well, I'm back.
In York I started off at The Maltings. I can see why it gets busy easily, it's tiny! Anyway, I had a pint or two and something to eat there before re entering the blast furnace conditions outside. For some reason I can't remember the name of what I had to drink, but it was dark and very nice anyway

(the darker the better IMHO. I have rather refined tastes you see).
I had heard of other real ale pubs, and was going to try and visit some, but I had forgotten where they were (or more, I don't know York for Adam!), so I just wandered around looking at things instead. Eventually, I came across a food and drink festival on one of the shopping thoroughfares (near to Jessops), and was able to sample some of the products on sale, including some from the Black Sheep Brewery and elsewhere. I finally ended up at another pub, the name of which I can't remember currently (argh!), and had a pint of Sneck Lifter, before heading back to the station. It was too hot to really do anything much anyway, and incidentally I only noticed The Yorkshire Tap on arriving back at the station (duh!) but not to worry, I'll be back!
I went to the Doric Arch once in London, but by the time I got there, it was just about time for last orders, so I had a pint of one of the Porters and got talking to someone about Father Ted of all things! All I can say is that that is one impressive model of 9F 92004 above the bar, and I'd happily go back again just to see it!
Yesterday, I was so knackered, mainly from the heat, so I slept in. Once up, I only had 3 or 4 hours before my train from Euston, so I went and visited St Pancras, where they were filming a drama for ITV about Bletchley Park, saw the new concourse/entrance hall at Kings Cross*, went to see the Shard and paid my usual respects to Mr Cuneo at Waterloo, or more, the mouse (if you know where to look). I did have some other things to do too as well, it wasn't just that, so the time went past quite quickly.
Nothing exciting, monumentally dull really, but, anyway, thanks for your suggestions, I'll remember them for next time when I have more time!
* - The pub and restraurant at Kings Cross (The Postal Yard or something similar) had a nice but small variety of ales, and seemed pleasant enough, but whatever you do, DON'T get food, it was definitely over priced for what I got! (Looking at the prices, I suspected it, but I was hungry and couldn't be bothered going anywhere else.... and it was too hot to even if I had wanted to anyway. I made the mistake so that you reading this don't have too). Bloody 'London Prices!'.
It did have a nice view of the trains though
