Just because you can make something at home, doesn't necessarily mean you should. Today's example? A laser 'shotgun' that uses a lens to combine eight 5W lasers into something that should definitely spice up your next PowerPoint.
The terrifying death machine was built by YouTuber styropyro, who has a long and detailed history of messing around with lasers. This particular rig uses eight 5W lasers, mounted with parallel beams onto a giant heatsink and powered with a big battery. The result is a fairly legit laser gun, capable of bursting balloons and setting fire to pieces of wood.
To put the 40 watts of laser power in perspective: the most powerful laser you can buy off the shelf is 0.005 watts; the US Navy's prototype laser cannon, powered by a warship and capable of shooting down drones, is 30,000 watts. In all fairness, a lot of the power of the laser shotgun is presumably lost, as the light is scattered somewhat by the optics. I still wouldn't want it pointed anywhere near my eyes, though.