A while back, Beste Miray Dogan designed Mapvelopes. Mapvelopes are mailing envelopes that are lined with your location (using images taken from Google Maps). She later teamed up with Teevio to create the site which allows you to print personalized templates.
More recently, Rahul Mahtani and Yofred Moik created a similar concept called Maps Envelope. In their concept, the map is displayed on the exterior of the envelope. They’ve also adjusted the design to include the locations (and addresses) of the sender as well as the recipient.