29 December 1928: birth of Bernard Cribbins, who played Tom Campbell in Daleks - Invasion Earth 2150 AD (1966) and Wilfred Mott in various Tenth Doctor episodes starting with Voyage of the Damned (2007) and ending for now with The End of Time II (2010); also Arnold Korns in the 2007 Eighth Doctor audio Horror of Glam Rock.
ii) broadcast anniversaries
29 December 1973: broadcast of third episode of The Time Warrior. Irongron's attack on Edward of Wessex's castle fails; the Doctor and Sarah infiltrate Irongron's castle, but are caught by Linx.
29 December 1979: broadcast of second episode of The Horns of Nimon. The Doctor and Romana end up in the maze with the teenage sacrifices.
ii) Date specified in canon
29 December 1758: Masetting of the climactic scenes of The Girl in the Fireplace (2006).