Retina scanner

Panasonic's prototype of a green home, the Eco & UD model home (Eco stands for ecological; UD stands for universal design) sports a host of energy-conserving appliances and could be built by 2010. CNET News.com's Michael Kanellos took a look during a recent trip to Tokyo.

Quit making funny faces or you aren't getting into the house, which sports a retina scanner instead of keys. The scanner can be fooled, but the odds are 1 to 1.2 million against it. You can also get in using RFID tags--the door can be programmed to automatically open as you walk up to it. When strangers come up on the porch, alarms go off.