Jeff and Danielle Smith sent a photo of themselves with their two young children to family and friends as a Christmas card, and posted the image on her blog and a few social networking websites. Then, late last month, a friend of Mrs Smith's was driving in his neighbourhood in Prague when he spotted the Missouri family's smiling faces in the window of a local supermarket. He snapped a few pictures and sent them to a flabbergasted Mrs Smith. It's a life-size picture in a grocery store window in Prague - my Christmas card photo!" said Mrs Smith, 36, who...