Joining “Postcrossing”

I saw a comment from someone about using Postcrossing, and it sounded like fun. The idea is that you ask for an address and send a postcard to that person. When they receive and register your postcard, they send you a postcard. Since you don’t actually know the recipient (yet, that is), you will be getting a postcard from a random place in the world. Pretty cool!
I sent a postcard to the founder of Postcrossing in Portugal as he is doing a presentation and needs a lot of post cards to hand out as examples.