A German eye-tracking company by the name of SensoMotoric Instruments (SMI) have built what they claim are the first pair of 3D glasses with full eye-tracking capabilities. They call the technology ActiveEye, and it combines eye tracking with 3D in order to give users the most realistic experience while using the glasses.
The glasses also have "6D" head tracking, along with the 3D eye tracking. The company partnered up with Volfoni to bring the 3D portion to the glasses, which feature active shutter technology that you see in a lot of advanced 3D glasses today. The 6D head tracking is there to detect gazes whenever the user turn their head to point toward an object.
The glasses offer real-time gaze streaming in world coordinates by measuring the position and orientation of the user's head within a defined space. The glasses are simply worn like a normal pair of glasses, and the eye tracking is made possible by two small cameras on the outer rim of the glasses while another camera records the field of view from the user's perspective. The three orbs on each side allow for the 6D head tracking, and they're detachable for easy storage.
While the Oculus Rift was a big hit at CES a few weeks ago, it's going to have some stiff competition sooner or later once virtual reality starts taking off. The eye tracking system from SMI supports Microsoft's Kinect, so it can already be used with technology that people already have. However, there's no word on availability or pricing for SMI's 3D glasses.