In hotmail you simply go to your hotmailaccount and click the "contacts" tab, there you select all the contacts you'd like to send a christmascard to and click on the "send mail" button. Now a new message screen will appear with all contacts in the "to" field.
If you do that please keep in mind not all your contacts may like their e-mailaddy visible to other ppl you send your card to, so i suggest moving them to the "Bcc" field. You can do that with cut and paste. There must be atleast one contact in the "to" field (all ppl you send the card to will see that one). If you don't want to give out anyones e-mailaddy you could put in another one of your own e-mailadresses in the "to" field, this way only your own is shown (you'll receive exactly the same as your contacts will..and you'll see none of the other e-mailadresses are shown)
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