If you're on the platform of East Ham underground station today, then you'll only have a cup of tea if you brought it with you. However, in the past, you could have bought it from this small brick building for a reasonable-sounding tuppence.
There is another treat here for fans of old signage: the ironwork bears the letters LTSR. These were the initial of the London, Tilbury and Southend Railway which opened the station in 1858. Its current user, the District Line, has served it since 1902.
Further viewing: see this ghost sign and all sorts of other interesting District Line features on the Secrets of the District Line video at Londonist.