50p

Hearing a knock at the door on Christmas Eve, the Fourth Doctor bet 50p it was carol singers. (AUDIO: Sepulchre)

Riccy Unwin gave the Ninth Doctor 50p in 2004 so he could pay for a cup of tea in a café in Cambridge, as the Doctor was trying to pay with bigger 10p pieces that had stopped being legal tender. (PROSE: Have You Seen This Man?)

Elton Pope exchanged "a quid for two fifties" so Jackie Tyler could use a washing machine at the Wash Inn. (TV: Love & Monsters)