Christmas carols what's yours?

There is an interesting thread going on over at facebook in respect of favourite carols as one of our on note local preachers has asked people what their favourite carols are as she might us them in a service she is involved in.
The question has taken us to discuss the merits of the two better known tunes for O Little Town of Bethlehem which are the original tune St Louis used more in the USA and Forest Green used more in Britain. Personally I prefer the original tune and might be tempted to use that in one of the three carol events I am planning. I also am very tempted to sing While Shepherds watched to the tune of On Ilkley Moor Bah Tat instead of the insipid Winchester New it is usually sung to or of course for purists you could sing it to Lyngham (O for a thousand tongues).

Any way here's a question for you dear reader - What's your favourite carol??