It appears that Sony was granted a patent in August 2005 on an optical magic wand idea. The description is for "an input device for interfacing with a computer" which "includes a body configured to be held with a human hand" that "includes a light emitting diode" that changes color in a way that "is capable of being detected" by "an image capture device." In other words, it blinks in a specific pattern that's detectable to a camera connected to a computer. I've heard of other systems that encode data into rapidly blinking LEDs (the most obvious is the infrared LEDs that power remote controls), but I think they're thinking of visible light. Maybe not, maybe it's all still IR LEDs, but the key is that it's detected by a general purpose camera, rather than a specialized IR receiver.
My prediction: soon, wands for everyone!
(The link to the patent is here and I was alerted of this by this New Scientist article.)
