Wicked Lasers, recently spotted putting frickin' laser beams onto sharks, is celebrating Star Wars Day with the release of a "LaserSaber" attachment that turns the company's powerful S3 lasers into lightsabers.
The LaserSaber is a 32-inch enclosed tube, and it works like so:
The laser energy that enters the LaserSaber is first diffused by a built-in optical element. Then the diffused laser enters the internal diffuser tube, which distributes the laser's energy evenly along the blade. Inside the diffuser tube, there is a metal sphere which is suspended permanently inside. This sphere's movement caused by gravity creates the beam grow effects. There is a magnet hidden in the tip of the blade, which causes the ball to magnetically lock in place. The magnetic lock can be disengaged by bumping the S3 laser with sufficient force.
It's only $99.95 right now, but it requires an S3 laser, which is significantly pricier.