"real time" PCR and other such techniques could make (will/is) something like this feasible... but you wouldn't need to get pinched or poked.
It could probably extract DNA in real time from your sweat or breath.
But then DNA will become just another identifier, because we'll be able to synthesize it too, and then amplify it again, use it to trick the machine, and so forth.
EDIT: leaving the error, but real time PCR is actually a lab technique. I meant basically super fast sequencing
Synthesize it? You can change your DNA in the future? Like they are looking at the blood going out from your body and they can fake that too? Future is amazing.
It could probably extract DNA in real time from your sweat or breath.
But then DNA will become just another identifier, because we'll be able to synthesize it too, and then amplify it again, use it to trick the machine, and so forth.
EDIT: leaving the error, but real time PCR is actually a lab technique. I meant basically super fast sequencing