Impulse Switch by AbleNet

Impulse is an EMG (electromyography) sensing electrode that senses tiny
muscle contractions. Using its patented technology, the Impulse detects and
wirelessly transmits the EMG signal to a Bluetooth receiver (included).
Specialized software then processes the activity as a traditional switch
"click". Combining this wireless power with popular accessibility programs
such as EZ-Keys allows users to fully control their computer with the
smallest of muscle activity. $2100 

http://www.ablenetinc.com/Default.aspx?tabid=361