Check the above Video and You got to know how much the technology is improved in this era.
A guy from India Developed that Product as a Mini Computer as his final year project in his college.
Currently that guy studying in MIT ,UK.His Name is Pranav Maistry
Features of that Mini Computer is explained in that above video Really cooool Features!!!!!!!!
Check It out
Very Soon he is Going to launch the product . It Cost Around 350$!!!! Very Cheap Right
One More Good news on the product is to be open source code,Yeah He is going to give the source code to all after the final product.
One more thing I heard is that the Structure of the product is going to be very small as button, because no one is ready to take weight in their necks so to overcome that some physical modification is going on that product.