What is it about information technology for MEMS that's so different? After all, we have been working on the problem of coordinating large numbers of devices for a long time - in research on distributed computation. One of the things that makes it different is the coupling to the physical world, with constant interaction and adaptation to the environment. For instance, if we are going to couple computation to the physical world, then whether we like it or not, the differential equations that govern the physical world are going to become part of our computer programs. So the challenge that MEMS places on information technology is not merely to coordinate lots of tiny computers, but rather to add a bit of computational behavior to materials and the environment.