Roland Piquepaille writes, "About eighteen months ago, I wrote about a tricycle with square wheels which needed a specially designed road. But now, Distributed Robotics, a company from Troy, NY, is developing robots with square wheels which don't need specific roads. These new 'cars' propel themselves on flat surfaces by taking advantage of gravity. This might sound crazy, but the inventors think it could lead to new robots and toys, and more generally to new micro-machines or MEMS applications." The square-wheeled robots are a joint project of Distributed Robotics and Global Composites, Inc. For more, see Roland's blog entry.