In the wierd spooky realms of quantum physics, it turns out you can play lots of tricks with the speed of light:
Robert W. Boyd, a professor of optics at the University of Rochester … demonstrated an optical fiber — a glass strand that transmits pulses of light — with a couple of odd characteristics:
A pulse of light shot into the fiber departs before it enters.
Within the fiber, the pulse travels backward — and faster than the speed of light.
And no, I don’t understand it either.