At Brother World Japan 2010, Brother Industries presented the AiRScouter, a head-mounted transparent display that projects images directly onto the retina.

This display uses the "persistence of vision" effect to project pictures onto the retina. It does this by shining a light, at a level of brightness that's safe for the eyes, and moving the light at high speed. The images projected on the retina are recognized by the visual sense, making it seem just as if they are floating just in front of the eyes.

Our dreams of an actually useful wearable computer have still yet to materialize, but the second-generation Kopin Golden-i concept -- now inconspicuously Motorola-branded -- is an interesting attempt. It's based around a head mounted, magnified SVGA LCD that is meant to be "glanceable" while the user remains aware of their surroundings. The Windows CE-chugging, OMAP3530-powered computer onboard is voice controlled and also motion sensing (for cursor control), and can hook up with other devices over Bluetooth, WiFi and USB. Of course, it remains to be seen if software can make something like this truly usable, but it certainly looks like the hardware is all there -- and the form factor isn't pure tragedy either.