Researcher are developing technology to translate thought into messages that can be wirelessly delivered. Funded by the US military ('natch), the aim is "synthetic telepathy," using EEG signals monitored non-invasively to communicate by brainpower alone. Apparently, this research goes back to the 1960s when a scientist used EEG to communicate in Morse code. Now though, the scientist are using brain scans to better understand how to detect and identify the brain signals. From MSNBC:
The Army grant to researchers at University of California, Irvine, Carnegie Mellon University and the University of Maryland has two objectives. The first is to compose a message using, as (UC Irvine professor Mike) D'Zmura puts it, "that little voice in your head."
The second part is to send that message to a particular individual or object (like a radio), also just with the power of thought. Once the message reaches the recipient, it could be read as text or as a voice mail…
Mapping the brain's response to most of the English language is a large task, and D'Zmura says that it will be 15-20 years before thought-based communication is reality.