For UK genealogists a gap in the records have been filled with the availability of telephone directories between 1880 and 1984. The 100 year rule on census returns means that there is little genealogical information available online for the 20th century. British Telecom through Ancestry.co.uk are now making available some of the telephone directories. Initially they are for London, Surrey, Herts, Essex, Kent and Middlesex, with the rest of the country following next year.
Apparently there are listed numbers and adddresses for some famous people including Bram Stoker, the author of Dracula, Sir Winston Churchill, Harry Houdini, Laurence Olivier and Ian Fleming. The mind boggles that in those days you could pick up the phone and dial Sir Winston’s home.
Background article on 24 hour museum website
Ancestry.co.uk’s page to search telephone directories