Apparently a "roomba" is some sort of artificial intelligence device that people actually allow into their homes under the deluded impression that they control it, rather than vice versa. Well, someone set up a long exposure camera in their room to try and track a roomba over the course of half an hour and this map of the thing's movements is what they came up with:
Complex signs - an attempt to communicate with other robots? Proto-military maneuvers? Hard to say. But as always, when it comes to robots, the best stance is a wary one.