People sometimes ask me if I have heard of any real neural interface systems (referred to as 'brain computer interface', or BCI systems) being used in the world today. Below is some interesting reading. Oh, and I have no affiliation with any of the companies listed.
For a primer on what neural interfaces are, and what they aspire to become, see Wiki's entry at http://en.wikipedia.org/wiki/Brain-computer_interface . It does a good job of outining the various technologies related to this field.
Cyberkinetics 'BrainGate Neural Interface System' - Currently in human testing, this system is comprised of a sensor, installed at the motor cortex of one's brain, and the brain impulses are then transmitted [possibly to a laptop or other receivers], interpreted, and used to guide mice, wheelchairs, TV remote controls, and other devices. Link: http://www.cyberkineticsinc.com/content/medicalproducts/braingate.jsp
An INFOWars piece: http://www.infowars.com/articles/science/brain_neural_interfaces.htm
Cochlear Implant: Bionic Ear: Check it out at the Wiki site http://en.wikipedia.org/wiki/Cochlear_implant or by Googling 'cochlear'.
National Institute of Health (NIH) Grant to fund research: August 2007 article at Medical News Today - http://www.medicalnewstoday.com/articles/78699.php