Fake London underground signs

This is a funny collection of pictures I bumped into yesterday. It seems the original source is this, posted here, but I am not quite sure, as they have been circulating for a year. As you can see, it is an enjoyable set of interventions on the signage system in London underground with some sharp messages and humorous hacks of maps, wayfinding signs, behaviour warnings,... The one who produced these interventions seems to be unknown (as far as I know), but hopefully someone took the time to take these pictures, which in fact, seem to be part of a guerrilla genre with the underground signs as its main stage. Unexpected and hard to see small changes can happen even when commuting and make you smile for a while.

These are my favourite ones:

The whole compilation here.