If you're talking about real, live industrial electricity where you're dealing with big motors, solenoids, transformers and all that rot, it ain't never gonna happen. You can correct the PF, but no one tries to pull it to 1.000; they just try to minimize it on one side of 0° or the other. If one did make the PF perfect, all it would take is a motor being loaded or unloaded a bit differently than it was when the PF was corrected to 1.000 and it would shift off again. So trying to achieve perfection isn't the least bit practical.
On the other hand, if you're just toying with simple electronics, a simple 1K ohm carbon composition resistor slapped across the 60Hz mains will exhibit a PF so close to 1.000 that to argue that it's anything but cannot be proved with any measurement equipment known to mankind.
If we insisted that all our water be as pure as that pure of a power factor, we'd be dehydrated in a matter of a couple of days.
Dean