It sounds like something from a robot-ruled dystopic future, but the "Crowd Farm" is anything but.
It's a sub-flooring system of blocks that depress slightly when stepped on and convert the energy of a crowd into electricity. In a place like Grand Central Station you'd harness the power of a lot of stepping. You'd be able to light the building! Power trains!
Sadly, no. The MIT architecture students who hatched the idea suggest using all that energy to "[light] up a sign about energy."
So it doesn't produce much power, but it's just another example of the ubiquitous waste of kinetic energy and we like the spirit of innovation.