The science-fiction sounding Audeo can apparently detect nerve impulses your brain sends to your vocal cords, and then translate them into meaningful electronic speech without a sound escaping from your mouth. While secret agents everywhere are presumably rejoicing at the idea, it's actually intended to help people whose disabilities mean they can't speak. Don't believe it? The designers recently demonstrated it by making a cellphone call at a Texas Instruments conference, and recorded it on video.
For the brain to send the right nerve impulses, it apparently requires the user to think about speaking in a particular way—one designer calls it "a level above thinking." Despite the learning curve this causes, requiring users to go through lots of training, it brings another benefit: you can intersperse talking normally with voiceless speech.
The company has been working on the technology for a while, starting by using it to control an electric wheelchair. For the time being, though, the speech system is a technology in its infancy. The processing delay is evident from the video, and it has a limited vocabulary of only 150 words and phrases. By the end of 2008, the company is hoping to release a new version that recognizes the phonemes that comprise normal words, effectively giving it an unlimited vocabulary. [New Scientist]