The argument is that someday everyone will have these. The article linked above quotes Cornell University Professor Hod Lipson: “In the future, everyone will have a printer like this at home. You can imagine printing a toothbrush, a fork, a shoe. Who knows where it will go from here?” Yes, I can imagine printing each of those things, but this printer will not print those things. This printer will print a custom Barbie head; which is really cool, to be sure–who wouldn’t want to have a Barbie with your own head (me?)–but frankly, I see this as being the Christmas present that you potentially unwrap and play with intensely for four hours and then put on a high shelf in the closet. There are just so many Barbie heads any one person needs, and at present, the system appears to be able to make only one of the three items mentioned by Lipson, and maybe not even that one. Of course, it can make parts for all kinds of things. I can imagine some pretty gnarly MP3 cases, and a micro-industry of mobile-phone modders. But I’m not sure bringing the cost down to $3,000 is going to make this a mass device yet. I’m one of the people who thinks it would be really, really cools to be able to have one of these, but the necessary price-point for me is still way off.