The Doctor's TARDIS, modeled after a police box, had a plaque on the outside stating among other things that advice and assistance were obtainable immediately. (TV: Boom Town [+]Russell T Davies, Doctor Who series 1 (BBC One, 2005).)
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The Fourth Doctor once offered Adric a piece of advice, telling him that everyone has to make sacrifices. (NOTVALID: A Moment from 'Doctor Who' 1)