A brief MIT Technology news item mentions a solution to the problem of making nanoscale machines that can swim in a fluid. The problem is that at the scale of nanotechnology, the effects of turbulence in water disappear, and any type of swimming robot that relies on traditional reciprocal motion can't move. Iranian researchers Ali Najafi and Ramin Golestanian, have come up with a novel method of propeling nano-sized robots in a fluid. The tiny robots consist of three rigid spheres linked by rods. A non-reciprocal, four-step periodic motion of the spheres moves the nanobot through the fluid. A more detailed explanation of the process can be found in a recent Physical Review Focus article and an animation of the motion is also available. At present only simulations have been done but it should be possible to build practical, molecule-sized swimming robots using this technique within a decade.