Black dinner plate size crab like object that moved on the ground.the object moved across the highway during a cold foggy night. If came from one side of the road towards the center cutting in front of our car. (Driver thought she hit it but no evidence.) The object was the size of a dinner plate and looked like a crab but moved like it hoovered not walked. It was black with two bubble like eyes on the top. There may have been, not sure due to the split second appearance, another stick like object that moved away the other direction. The object had "legs" that I can only say were not functioning to move it. First thought was it was a creature or something being blown across the road however there was not a breath of air, just very cold (10 degrees at most). It did not move in a this world order. It may have had a gray or silver ring around the outer edge. This all happened in a matter of two to three seconds. Driver and myself, a back seat passenger leaning over the front seat, saw the object and both saw the sam! e thing as we discussed it. A visit to the site the next morning turned up NO sign of tracks or anything that would suggest something had been there.