In a seriously awesome piece of technological prowess, the N900 can make the call you were thing about without you have to touch a thing. Manipulating the N900 from the mind has been made possible by a Qt based application called ThinkContacts, paired with the NeuroSky MindSet.
The interaction between the user and software is done via brainwaves and for this to happen the user needs the NeuroSky Mindset which reads the user’s brainwaves, uses an analog-to-digital converter and sends the digitalized information via Bluetooth to the phone. The byte sequence, called packet, sent by the headset is then translated into the user’s level of meditation and attention by using an algorithm provided by the headset’s company. Once all of this is done, the signal is passed on to the ThinkContacts app via bluetooth and it places the call.
To get an idea of how it works, I recommend that you check out the following video.