Facebook loves to test experimental new features with small groups of its users, and today brings another one: snail mail postcards made out of your Facebook photos. The social network is teaming up with Sincerely, the guys behind Postagram, to process and deliver the postcards. In order to place an order, you click the "Mail Postcard" button next to the "Tag Photo" button inside the Facebook photo viewer. You can write a message, attach an address, or ask a friend for their address if you don't have it. One thing you can't do is send public photos or photos from Facebook Pages.

Like many current Facebook features, postcards began as a hackathon project and will only roll out worldwide if the random group of users Facebook selected buys some postcards. Facebook hasn't even established a price point yet — it plans to try out a few options within the already random group of guinea pig users and see which one works best. Postagram for smartphones has an odd allure to it, but we'll have to wait and see whether sending mail from a computer is an endearing novelty or another Facebook test that will never see the light of day.