In a future of pervasive augmented reality (AR), AR systems will need to be able to efficiently draw or guide the attention of the user to visual points of interest in their physical-virtual environment. Since AR imagery is overlaid on top of the user's view of their physical environment, these attention guidance techniques must not only compete with other virtual imagery, but also with distracting or attention-grabbing features in the user's physical environment. Because of the wide range of physical-virtual environments that pervasive AR users will find themselves in, it is difficult to design visual cues that "pop out" to the user without performing a visual analysis of the user's environment, and changing the appearance of the cue to stand out from its surroundings. In this article, we present an initial investigation into the potential uses of dichoptic visual cues for optical see-through AR displays, specifically cues that involve having a difference in hue, saturation, or value between the user's eyes. These types of cues have been shown to be preattentively processed by the user when presented on other stereoscopic displays, and may also be an effective method of drawing user attention on optical see-through AR displays. We present two user studies: one that evaluates the saliency of dichoptic visual cues on optical see-through displays, and one that evaluates their subjective qualities. Our results suggest that hue-based dichoptic cues or "Forbidden Colors" may be particularly effective for these purposes, achieving significantly lower error rates in a pop out task compared to value-based and saturation-based cues.