It seems that the Wii's sensor bar isn't entirely necessary to use the Wii remote's pointer functionality. An intrepid Wii user has posted an online video showing intermittent pointer reception using two TV remote controls in place of the sensor bar.
Apparently the Wii sensor bar is actually a transmitter for a dual IR signal that gets triangulated by the Wii remote, not a receiver for a signal that comes from the remote. This revelation would seem to suggest that any correctly positioned, consistent dual IR source can be used in place of the official Nintendo provided sensor bar. With this information in hand, how long will it be until we see hackers rigging up their own custom sensor technology?