The postcrossing official forum where you can chat with other members of this project.
Postcrossing gallery for posting pictures of the received postcards.
Postcrossing twitter for quick updates on the project.
Postcrossing Facebook group for the users of this big social network.
An orkut community around postcrossing.
A page for the Postcrossing fans in Facebook
Universal Postal Union (UPU) recommendations on how to properly format an address in each country
A website with translations to several languages of common sentences used when writing a postcard
Allows you to track your Euro bills around the world.
This project is making 1000 journals travel around the world.
A French project that allows it's users to exchange surprises.
The Letter Writers Alliance is dedicated to preserving handwritten letters - all sorts of goodies related with that!
The postsecret project allows people to reveal their secrets using postcards.
A blog around mail art that exhibits postcards sent by snail mail to them
A tumblr blog of postcards mail with the answer to the question: "what are you doing, you know, more generally?"
A good website for buying or selling vintage postcards and other antiques.
Information for postcard collectors and dealers from the postcard traders association.
