Well it does sound as though you don't want to post any! If you don't then just don't. You could put a note in each card this year saying that from next year you won't be sending any cards and will instead be making a donation to charity. Or just don't send any next year! Or prune your list to people you really do want to stay in touch with, I lost about 30 people on my list by just thinking about each person, how long it was since I'd last seen them, and how much I wanted to stay in touch with them. But as been pointed out, you can get packs of cards really cheap, and send any 2nd class. And remember, stamps are no dearer this year than they were last year!