E.T. the Extra-Terrestrial

E.T. the Extra-Terrestrial was a film which made Sarah Jane Smith cry. (EDA: Interference - Book Two) She later stated that it was her favourite film. (VD: Moving On) She also had an old ET clock by her kitchen sink. (EDA: Interference - Book One)

In 2006, after a spaceship landed in the River Thames, people celebrated all over London, especially on the Powell Estate, where some residents put up a banner saying "WELCOME E.T.", a reference to the main character of the film (or possibly just to extraterrestrials in general). (DW: Aliens of London)

When Florence Finnegan, a Plasmavore who was hiding out in Royal Hope Hospital, revealed that she was an alien, the Doctor (himself posing as a human) jokingly asked if the hospital had an "E.T. department". (DW: Smith and Jones)

When Clyde Langer mocked Rani Chandra's habit of believing aliens were behind unusual events, he jokingly conjectured that his bike had been stolen by "E.T. the ASBO". (SJA: Mona Lisa's Revenge)
 * In real life, the director of E.T., Steven Spielberg, once held the theatrical film rights to Doctor Who when he was allied to Universal Studios. The result of this holding was ultimately the Paul McGann telemovie.