It would be the ultimate technology to possess for the Goerge Orwell’s Thought Police or the ‘precogs’ in Steven Speilberg’s Minority Report. Researchers monitoring brain activity can now determine what action a person is planning before he carries it out.
Although it is currently only possible to know what someone is going to do just moments before it happens, the implications of the breakthrough are huge.
Police, for example, would love to know what a criminal is intending to do during a tense armed stand-off.
Or like in Orwell’s 1984, it could be used by Thought Police for psychology surveillance to find and eliminate members of society who are capable of the mere thought of challenging ruling authority.
Lead researcher Jason Gallivan, of the University of Western Ontario, said: ‘This is a considerable step forward in our understanding of how the human brain plans actions.’
Over the course of a one-year study, volunteers had their brain activity scanned using functional magnetic resonance imaging (fMRI) while they performed one of three hand movements – grasping the top of an object, grasping the bottom of the object, or simply reaching out and touching the object.
1984 is now ! 
We’re still a very long way from a practical mind-reading technology, but I have little doubt that something like you describe will eventually be available – give it 20 years or so.