Hey, I have an idea - for Niina and others from Europe - Why not mail one big envelope to one "point person" in the US with all the cards for the US folks addressed and ready to go inside? If you did that, you'd just have to pay the expensive postage for one, and then the "point person" here could put US stamps on the others, and you'd just have to reimburse the "point person" 37 cents for each one inside the envelope!

It'd be almost no work for the "point person" - just taking them out of the envelope, putting stamps on, then mailing! No one would get the European postmark, but they'd get your card, greetings, pictures, whatever!