From the Nanorex online gallery:
This worm drive assembly designed by K. Eric Drexler, Josh Hall, Ninad Sathaye and Mark Sims includes 11 components totalling 25,374 atoms. The animations below have been created from simulation results using NanoEngineer-1 Alpha 7, taking just over 370 hours to complete on a Dell laptop running WindowsXP. It is the largest model ever simulated with NanoEngineer-1. More information about this model is coming soon.