"As Time Goes By." was the title of a brillant BBC TV series.
Starred Judi Dench & the guy from Yes Minster I think...
That slow subtle hysterically funny British sense of humour - about the guy and the girl who met in England in WWII, then drift apart, until they bump into each other years later.
The song fitted that very well as the theme song.

'The Mountains of Mourne' is actually a very funny song - subtle british humout again - combined with a wistfulness. that's why it was so damn popular for so long.. Pretty tune too - heard a wonderful song about using it about the REAL Molly Malone Statue... :-)

Robin