Future UnCERNtainty

So, apparently the world might end tomorrow. Out of all the screw-ups I ever made in the lab, it's safe to say nothing I did was ever likely to have that kind of effect.

I'm actually having a few days off with no fixed plans. It occurred to me that something I could do is find someone else at a similarly loose end and meet at the Underground. If we both board the Circle line, but headed in different directions, what would happen at the point at which our paths cross, if we managed to make eye contact? Would the Underground grind to a halt? Would Bob Crow be silenced forever? Would Boris's hair get even wilder?

But do I really want to fork out £5.90 on a travelcard if the world's going to end? Does PAYG work in a black hole?