Meantime Beer Box, SE10 0DX
It's a small, box-like building in a pedestrianised precinct outside the O2. The downstairs contains a bar and not much in the way of seating. If you go outside there are a handful of tables and a scaffolding style metal staircase which takes you to the upper room. It has three tables, two beanball games, electric heaters and astroturf flooring. From looking at their website it seems that the roof is taken off in the summer but it was definitely covered during secretlondon's November 2016 visit.
They have the full range of meantime beer on draught for £5.50/pint. It is all keg, there is no real ale. They also have some in bottles.
Also outside are the toilets which we didn't visit as the ones in the O2 seemed a better bet.
Accessibility: I think there was a ramp to enter but there is only stairs to the upper area. The toilets are unchecked but the O2 has an accessible one.