One is a backpack-sized portable ADS that uses microwaves to roast your skin, creating what the Pentagon gingerly calls a "repel response"—in other words, OWOWITBURNSOWOWTURNITOFF. They say it causes no permanent damage, but there haven been cases of second-degree burns.
And then you've got the PhaSR, that Starship Troopers-looking laser rifle above. Not only does "dazzle" you with lasers—not the kind that'll make your sight any better—it has a infrared beam attachment to burn your skin too, which is more currently practical than the microwave-based pain beams, though the latter penetrates clothing better. The National Institute for Justice is testing it "in various scenarios, which may include prison situations as well as law enforcement."