I would like to see some 3D printers integrated with a scanner large enough to do faces or similar-sized objects with a software suite that could do the 3D printed equivalent of a paper cameo or cake/jello-mold. Like a little faux "ivory" cameo would the the kind of chachkis I would actually want to take home from some fair or amusement park. Even software (like an effect in CS) that does caricatures would be so sweet.
Funeral masks could be a really baller custom to have return.
If this exists it evades my Google-Fu so please link to it. If this does not exist and you like it and have the will to make it happen then please do. I want to play with that sort of stuff.