Last year and the year before, we bought Help for Heroes - this year (so far) I have bought Royal British Legion, and some combined Charities cards from Waitrose. My 2013 calendar is from the RNLI.
We have a charity card stall in the centre of town and they sell for 30 or so different charities.
Last year I went for those being sold for the Deaf Children's Society, another time I chose a local charity. I looked through them all the other day but didn't buy, but I will probably go back and chose when I get there.
I only ever buy the RNLI cards. Primarily because a friend of mine was once the coxswain of the Girvan lifeboat in Ayrshire and the stories he told me of the things they have to do were alarming, to say the least.
I've been buying them for some thirty-odd years and will continue so to do.
I live in London, and am more than 40 miles from the sea, but the RNLI is my favourite charity.
I always buy charity Christmas cards, but only from charities that mean something to me - Alzheimers Society as my late father was a sufferer, National Autism Society as my friend's son has Aspergers, and Macmillan Nurses because they were fantastic at helping a friend when her husband was ill with cancer.