GE Engineer Matt Gluesenkamp decided that to celebrate the 50th anniversary of the laser, he'd destroy any hope you ever had of lightsabres becoming a reality. Hey, Matt, next time just blow up some balloons or something.
Gluesenkamp spends a good amount of energy explaining the various reasons why lightsabres could never be real. The main hurdle seems to be, well, basically everything. The death blow summary:
It seems quite impossible to create a lightsaber, as seen in the Star Wars films, using existing technologies, materials, and physical laws.
But other than that, we're still on track, right?