This being The Papercraft Post, I've made some postal-themed cards to celebrate the occasion. The card itself has an envelope theme - the address side bears a WCMD greeting - the flap side has a WCMD version of the Papercraft Post watermark.
The envelope for the card is meant to look like a messenger bag-style mail pouch. There's a version with a strap (for hand-delivered messages). For a postable version, just leave off the strap.
Here are your free downloads:
The envelope is pieced so it can fit onto A4 paper. Just stick the flap onto the top edge. If you are making the strap version Messenger Bag Envelope, stick the strap ends inside the envelopes before you join on the flap. The buckles are decorative only - just slip them on. A dab of glue on the centre bar keeps them in place. Seal the envie with a glue dot under each of the buckles.
Happy World Card Making Day!