i will give a few:
9/11/01: i was watching a rerun of Little House on the Prairie(the episode was "The Lord is my Shepard" (part 2) but the other TV(maybe because of MNF the night before) was on ABC when the first reports came in was really upset when the two towers collapsed. the image of watching Laura on the mountain praying while the on the other TV seeing the both towers in smoke as haunted me for a long time.
were anyone of you watching a program and something historic happened?