The advent of Internet communication has seen much personal correspondence move from paper-based into digital form. But while the Internet is often associated with the decline in paper-based communication, it also provides opportunities to exchange traditional ephemera in new, exciting ways. We present here an analysis of Postcrossing, an online system that facilitates the sending of non-digital postcards among random strangers. Via a survey study of Postcrossing users, we elicit six key factors that contribute to the Postcrossing experience. We consider how these elements might be carried over into other digital communication technologies.