Currently, Moo only handles these delightfully ingenious “calling cards” made (full bleed, apparently) from your cropped photos on Flickr. It’s stupidly easy to use, works like a charm to set up, and if you have a Flickr Pro account (like I do), you can try it out for free and get a ten-pack of cards made from up to ten different pictures. You can customize the text on the back as much as anyone needs to, and it’s a snap. Four main steps, and you’re done!
I hope to post an update when I receive my cards “up to ten days” from now.