Tube whiteboards are used for service updates, inspirational quotes and, er, barbed comments aimed at Boris Johnson's transport policy.
Quote of the Day for @MayorofLondon at Clapham Sth station ahead of next month's strikes. @RMTunion
Channel 5 journalist Jack Leather spotted this sign at Clapham South tube station this morning.
London Underground staff aren't happy that Boris Johnson has gone back on previous pledges and decided to close all ticket offices, which will result in hundreds of job losses. Johnson reckons customers can get by without ticket offices and has pledged to open several tube lines for 24 hours at weekends.