Why do people have to know one is donating to charity except to inform them what a Wonderful Person one is? Why not send cards as usual and donate to charity? Or send "charity" cards? I normally send cards to people I don't see very often; it just means you've remembered them and value them. Some, but not all, of a group of pub mates have taken to sending (i.e. dishing out in the pub) Christmas cards to each other, which I think is barmy. I don't do it and it's done me no harm whatever.