The potential of genuine nano technology is only limited by our imagination.
25-50 years from now Star Trek will look sillier to our grandchildren than the old 1930's Buck Rogers serials look to us.
The Borg are an ugly joke compared to whats possible.
I think the future of medicine will be a set of machines, that can internally produced, in such numbers that every cell in the body could have it own robotic controller. Each of these robots could have greater computing power than todays mainframe computers.
Right now scientists are using inkjet technology to build up layers of cells to produce artificial skin and they are looking to use the same technology to produce complex 3 dimensional organs. 25 years from now cloning could be a technology that is considered old fashoined and obsolete.
Finger printing, retinal scanning even dna will be rendered useless.
The proverbial fly on the wall will be something to fear, because insects controlled by micromachine will be used to hunt and eliminate all trace of terrorists.
Laws and legal precedents from today will be used in ways never imagined by the average citizen.