Saving a life by mixing man and machine has had varied results: Darth Vader tormented a galaxy, RoboCop saved a city. Still, I'm in no way hesitant about the Brain Computer Interface. The system, developed by researches in Berlin, allows for a direct dialogue between a person's brain and a computer. On display at the CeBIT trade show in Germany this week, the "mental typewriter" translates thoughts into cursor movement. Signals from the brain, measured by 128 electrodes affixed to a subject's scalp, are dissected by a software program, picking out specific instructions amongst a mass of information. In the long term, the researchers hope a brain-controlled device will allow people with severe disabilities to communicate with the outside world. Currently, it takes 5 to 10 minutes to write a sentence with the system; that's obviously too slow for everyday use, but as the technology improves, the device could give the paralyzed a voice. Other researchers in Germany and the United States are working on similar systems.