This is probably the closest thing to the lightsaber we've ever seen. Well, if a lightsaber had "canyon-sized blood-grooves" down the side and was "designed for penetration."
Ethan Wolff-Mann is the Gear editor of Supercompressor. He is not sure of a giant switchblade's legality, but his gut says it may be more permissible due to the irrelevance of the concealment argument. Follow him on Twitter @ewolffmann.