A computer or peripheral device that has been designed and built to military specifications for field equipment (that is, to withstand mechanical shock, extremes of temperature and humidity, and so forth). Comes from the olive-drab "uniform" paint used for military equipment.
As the deep tone responded to his pressure on the big rubber bulb the men in the green machine looked back.
Those in the green machine seemed unaware of the approach of their pursuers.
Larry steered it directly in front of the green machine, and kept just far enough in advance to avoid a collision.