One of the few remaining things that makes computers big is the keyboard. Thumbable keyboards on PDA's are OK, but what we really need is a transparent way to interact with the net-enabled technology we'll be wearing within this decade. Speech-based interaction is transparent, but the world would get pretty noisy if we're all talking to ourselves as we walk (and surf) down the street. The solution: subvocal input. It's not ready yet, but it's clearly on the way:

"In preliminary experiments, NASA scientists found that small, button-sized sensors, stuck under the chin and on either side of the 'Adam's apple,' could gather nerve signals, and send them to a processor and then to a computer program that translates them into words. Eventually, such 'subvocal speech' systems could be used in spacesuits, in noisy places like airport towers to capture air-traffic controller commands, or even in traditional voice-recognition programs to increase accuracy, according to NASA scientists.

'What is analyzed is silent, or subauditory, speech, such as when a person silently reads or talks to himself,' said Chuck Jorgensen, a scientist whose team is developing silent, subvocal speech recognition at NASA's Ames Research Center, Moffett Field, Calif. 'Biological signals arise when reading or speaking to oneself with or without actual lip or facial movement,' Jorgensen explained.