Few things can actually travel faster than light. One among them is Cherenkov radiation.
These are electromagnetic radiations emitted as electrons by the spent nuclear fuel particles when it is placed under water for quite a few years in the spent fuel bay in a nuclear power plant.
The characteristic blue glow is due to emission of this radiation. Note here that the speed of Cherenkov radiation is greater than light only in water, where the VELOCITY OF LIGHT HERE BECOMES 0.75 x 3 x 10^8 m/s.