Spotted on the Ramsgate to Victoria line.
On the Waterloo to Exeter line.
And this one on South West Trains.
The stickers are being handed out on comedian Mark Thomas' current UK tour, entitled 100 Acts Of Minor Dissent. There is a Twitter account, @100acts, that chronicles other similar small acts of rebellion.
And the Mail's response when I tweeted one of these pictures?
@lukelewis @branchenergy OUCH