I am currently located in Europa and I had them ship a potato-message to my boyfriend in the US. It was a cryptic message that only he would understand and he would instantly know that it is from me. He called my on skype and we both were in stitches.
Not really a service that the world needs, but a fun way to say hello. International shipping/payment worked well and I was surprised how quickly the potato made it to my bf's home. Not sure about the nutrition quality of the potato though, as my bf didn't eat it (yet).