Pubs. My favourite subject. I'm a pub bore. I even
write a blog about them.
One of the best pubs in Britain is The Harp, just off Charing Cross road near Trafalgar Square post office. Supremely good ales, first-class service, sausage sarnies. Gets busy but worth it (also an upstairs that nobody notices and is usually empty). This is my favourite pub in central London. I've been dozens and dozens of times and loved every visit.
There's also the Mitre, down an alley off Hatton Garden at the Holborn Circus end. Look for the Bishops Mitre on the lamp post.
If you don't want to pay 'London Prices', any of the Samuel Smith pubs are worth a look. Old Brewery bitter is a bargain - best of the lot is probably the fine Victorian gin palace that is the Princess Louise nr Holborn Tube, or the Cittie Of Yorke further back down High Holborn. Another is the Cheshire Cheese on Fleet Street.
Honorouble mentions go to the Lamb And Flag in Covent Garden, Market Porter at Borough Market (and if you can be bothered with the walk the nearby-ish Royal Oak on Tabard Street). Outside Euston station is the new(ish) Euston Tap - an American-style 'craft beer' place. Good prices, interesting and unusual beers. Similar is Cask, off the beaten track (but fairly handy for Tate Britain) in Pimlico. Well worth a visit if you're in the area. The Cross Keys in Endell Street (Covent Garden, parrallel to Neal Street) is also good.
Cheapest cup of coffee in London is at the Algerian Coffee Stores on old Compton Street in soho. Haven't been in for a few months, but an espresso is still less than a quid - and a cappuccino not much more. You have to drink standing up, German-style though. For an 'unsual' meal, you could try the
timewarp that is The Lorelei on Bateman Street - very good, cheap pizza (and chips!) - and coffee.