In June 2004, surgeons implanted a device containing 100 electrodes into the motor cortex of a 24-year-old quadriplegic.. Each electrode taps into a neuron in the patient's brain. The BrainGate allowed the patient to control a computer or television using his mind, even when doing other things at the same time.
The chip's 100 electrodes can tap directly into 100 neurons, and theoretically can transmit whatever each of those neurons is communicating. The learning curve is apparently rather short compared with other systems used by paralysed people, such as eye control or tongue-control.
Now, when the direct communication between mind and computer gets to be two-way, you won't need a keyboard OR a screen. In fact, your PDA might simply become a wireless supplement to your mind. And if it's a PDA connected to the web, your potential mental capacity is scary, to say nothing of your ability to communicate by thought -- imagine the future of IM. But I'm getting ahead of reality just a bit. Or am I?