Sadly, this is probably just a camera trick involving smoke and LED lights.

But what if a man actually built a working Star Trek phaser? What if he used it to pop balloons? What if he brought it to a bank and took everybody hostage? What if he used all of the money to build more Star Trek devices, like a working spaceship with its own holodeck? What if his evil, bearded twin from a parallel dimension came out and challenged him to one-on-one combat for rulership of the universe? What if he won? What if he turned us all into tribbles?

Guy Builds A Star Trek Phaser [YouTube (thanks, Terrence!)]