For those who _need_ a bigger death ray ...
Check out the book "Build Your Own Laser, Phaser, Ion Ray Gun and Other Working Space Age Projects" by Robert E Iannini. Among other things, this 1983 book can tell you how to build a 30 watt CO2 laser. The author cautions: (1) always have a visible laser (such as one of those pointers) aligned with the infrared CO2 laser, so you can see approximately where the beam goes; and (2) stay out of the beam! He notes that he accidentally walked through the beam and instantly cut a slit in the leg of his jeans. 30 watts is definitely enough to cause damage, even if poorly focused. CO2 lasers can be built in almost any size - IIRC the length of the chamber determines the power of the output. Car companies use big CO2 lasers for welding cars.
I will just add that it is illegal to sell lasers of that power at least in the US, for good reason. I don't know if it's illegal to buy one or build one. At least if you have the technical chops to build one, you're _probably_ not so cognitively challenged that you would use it unwisely.
Biting the hand that feeds IT
