All of Robert Goodin's postcards are printed on actual wood and can be safely mailed with a standard postcard stamp. They are also very durable, will not break, use less wood than a paper postcard, and the wood is sustainably harvested. The grain will vary on each card. They measure 4" x 6".
"The Monkey and The Crocodile"
This image is taken from the comic Robert drew of the same name. It's printed on cherry wood.