I’m reading Hacking Matter by Wil McCarthy, and am looking for the killer app for programmable atoms. Sure, it’s great that you can switch from copper to iron, but how often do you need that? And a house that can turn invisible is swell, but that’s entertaining for about five minutes. Granted, that’s longer than I could stay interested in Lost or American Idol, but is it worth reading a book about?

One possible app I haven’t seen so far is the possibility of using programmable atoms as enzymes. Instead of giant refineries and chemical processing plants, you could produce any kind of chemical reaction by simply running the basic chemicals along wafers of programmed artificial atoms. Now, that would be magic, but I see no mention. Is that because the developers of programmable matter aren’t thinking in terms of chemical engineering, or because there’s no prospect there?