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 have 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."
Meaning we can look forward to videos like this one, but with a sweet Halo rifle instead of a dinky taser dishing out the pain: [NewScientist]