Everyone knows that Sherlock Holmes lived in Baker Street (221B to be precise) but so did William Pit the Younger. In 1783 he became Britain’s youngest Prime Minister at the age of 24. People still write to Sherlock Holmes, despite being a fictional detective, and the current occupants of 221B, Santander Bank, employ a secretary to deal with his mail.
Even more interesting and just a few doors down is the former flat of John and Yoko.