(3 of 3)
"That's the key to the illusion," says Lanier of VPL, which supplies NASA with its DataGloves, and has developed its own EyePhones goggles and full-body DataSuit. "Once you reach a certain threshold, your brain suddenly flips into believing that the virtual world is the real world." Lanier used the power of this illusion to teach himself to juggle. Donning Data-Gloves to control some computer-generated balls, he began tossing them around in slow motion and then gradually sped up the simulation until he was juggling at a normal pace. Lanier envisions the day when architects will not just wander around computer- generated buildings but will also move walls and rearrange windows simply by reaching out and grabbing them. Eventually, he predicts, couples will be able to visit artificial tropical islands together. What they do there will be limited only by their imagination -- and the power of their computers.