I was never a part of one because my old forum became redundant and everybody went on with their important lives.
But there is such a strong community here!! Whose interested in exchanging christmas cards this year? We should make the deadline for mailing them in mid-November to allow for international mailing. Only one, or two members (at most), will have access to all the addresses for privacy reasons. This member will randomly pair up other members for christmas card exchange. This means you only send one card and receive only one card unless you specifically state otherwise. (for example, if you want to send a card to four members you might not necessarily receive 4 cards in exchange since not everybody is willing, or is able, to send more than one)
I volunteer myself to pair up addresses if nobody else wants to. I just really like the idea of a christmas card exchange!!!