The 50 Best Inventions of 2009

Plenty of people's Twitter feeds appear to be connected directly to their egos, but one scientist's is actually wired to his brain. In April, University of Wisconsin doctoral student Adam Wilson — working with adviser Justin Williams, above — tweeted 23 characters just by thinking. He focused his attention on one flashing letter after another on a computer screen while wearing a cap outfitted with electrodes that monitored changes in his brain activity to figure out which character he wanted. His efforts spelled out "USING EEG TO SEND TWEET," among other messages. The feat marks a major step forward in establishing communication for people with "locked in" syndrome, which paralyzes the body, except for the eyes, but leaves the mind alert. For now, though, it's slow going: with the speediest brain tweeters reportedly managing just eight characters a minute, it's a good thing they're limited to 140.