Hmmm - it'll need to be someone with access to the local hostelries, as, being in the heart of the City, a fair number of hostelries in the locale are only open Mon-Fri.
Martin Driver would know one as he's prteviously organised a meet for a Barbican gig - which pub was it, Martin? And would you recommend it?
As you say Chris, many of the pubs in the area are closed at weekends, so there is not a great choice of options in the vacinity of the Barbican. "The Old Red Cow" located at 71, Long Lane, is the pub we met in the last time.
Directions; turn right as you exit Barbican tube station, then immediately right into Long Lane, the pub is 100 yards on the left.
They also serve food.
http://www.fancyapint.com/pubs/pub67.html