Watching Bad Universe on DVD a couple of days ago, on one episode Phil Plait visited a facility that produced self replicating machines. A 3D printer was set up to fabricate copies of the components it was built from which could be assembled to create an exact replica of the original machine. What would happen if the process was left to run indefinitely, would you evenutally get evolution acting to constantly refine the design and if carried out long enough an "artificial" life based ecology?