Ziferblat Cafe, London – where drinks are free, but you pay 3p-per-minute to be there

This is an interesting idea – as long as the coffee is good then it could well be worth visiting the Ziferblat cafe.

http://www.theguardian.com/travel/2014/jan/08/pay-per-minute-cafe-ziferblat-london-russia

I wonder if they are open 24 hours a day and have comfortable chairs?