Spotted in London's Hammersmith Broadway area by Joe Harland:
It is, of course, a reference to the opening credits of 'Bottom':
And as has been pointed out, a still from that opening footage is now particularly poignant:
(pic via Russell Hughes) pic.twitter.com/iyPUfgk54v— Viz Comic (@vizcomic) June 9, 2014
RIP, Rik. You will be sorely missed.