"It's called the Agony Matrix. Direct neuro-stimulation of pain receptors... All of them. Imagine the worst pain you have ever felt in your life times a thousand. Now imagine that pain continuing forever. ...Oh, that's right. You don't have to imagine."
There's a special place in the heart of Sci Fi and Fantasy geeks for the Agony Beam, usually because it's carved that chunk out of our collective heart and crawled into the resultant cavity. Despite being an old school staple that's used to the brink of cliche and back, it still sees widespread use and continues to serve a useful purpose: causing PG-rated pain on victims, much like an evil version of Stun Guns.
Along with its big brother the Death Ray, the Agony Beam is a staple in the armoury/spellbook of every Evil Overlord and Evil Sorcerer worth their salt. It is the Swiss Army Knife of a villain's arsenal: at low levels it enforces obedience when defiant prisoners are ordered to Kneel Before Zod, it serves as punishment for incompetent minions in place of more lethal measures, and prolonged use or higher settings work as a (bloodless) torture method, and when in excessive use or high power settings it can drive one mad or outright kill the victim. Usually it's depicted as a beam that emanates either from a gemmed ring, a staff, a ray gun, or even a miniature lightning storm. This last one works wonderfully as part of the lightshow when the villain gets Drunk on the Dark Side. When the victim is a major character, the Agony Beam is usually accompanied by Evil Gloating.
As mentioned earlier, the Agony Beam is rated PG. This is because, like the Death Ray, it's very "clean", leaves no scars, and is much less squicky than comparabletorture tropes while being just as effective. Like Electric Torture, the lack of physical injury means the hero will be able to continue in the plot once it's over. That said, authors can turn it Up to Eleven and cause such unbearable levels of agony that it can break the victim's mind. All things considered, even at low settings the Agony Beam is the moral equivalent of a Dog Kicking Ray, a fact usually reinforced by the wielder getting off on using it. It's not going to be just rated G because... well...it'd be a pretty dark prospect for little kids.
When turned on a hero, they will demonstrate their mettle by not bending knee until it's at least two settings higher than necessary. Of course, at one point you can expect the villain to have their weapon turned against them (usually thanks to mirrors and/or silver trays) and do much less well.
Closely related to Electric Torture. The "Increase the intensity!" sample conversation there applies for this too. May be part of a Robotic Torture Device's arsenal. If used in a device attached to keep someone compliant, it becomes a Shock Collar.
Can be a cause of I'm Having Soul Pains.
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In Mazinger Z and Mazinkaiser, the villainous Baron Ashura often uses this, in the form of a staff that shoots a blast of (usually) non-lethal electricity. Dr. Hell also uses an identical staff to punish Ashura when he/she/it screws up (or a device on his belt also shoots one).
The manga and anime Naruto brings us Tsukuyomi, a Genjutsu that is instantly cast and lets you live through 72 hours of intense mental/physical pain in a couple of seconds. Both victims in the first part of Naruto were out for a couple of weeks and needed the best medic the Narutoverse has to heal them. In the second part the Big Bad wants to use it on the world.
Tsukuyomi isn't automatically painful; the user can subject the victim to whatever he feels like, but torture is the typical choice. Itachi has used it to show his own memories to another person, while the Big Bad intends to use it for Mind Control instead, by casting it permanently on everyone.
The Slave King often uses this in The Great Slave King on anyone who has particularly displeased him.
In the movie adaptation of The Crow, Eric defeats the Big Bad with this trope by Agony Beaming his fiancée's experience of being gang raped, beaten and dying from her injuries over 30 hours later into the Big Bad, rendering the Big Bad incapacitated and vulnerable to the final death-dealing blow.
Emperor Ming in the 1980s Flash Gordon movie used this on Flash several times. Ming had a much less impressive looking version back in the 1940 serial.
Sith in Star Wars use Force Lightning both as an all purpose offensive weapon and as a means of torture. The Expanded Universe has a rather nasty example: Chiss weapon, the Charric; it has 3 settings: Kill, Burn and PAIN! Guess which one doubles as stun.
In Fortress, when prisoners arrive at the Fortress (a giant underground prison), the last part of the processing involves the prisoners being forced to swallow a device called an Intesinizer, which acts as an Agony Beam if they break the rules. For more severe infractions, it explodes.
Ghostbusters: "Are you a god?" "....no." "THEN DIIIEEE!" :zaaaaaaaaaaap: Clearly Gozer was pulling her punches here; since it mostly just knocked them down, almost blowing them off the roof of the apartment complex. According to the novelization, the proton packs absorbed most of the energy and nearly overloaded as a result.
The second film had Vigo disabling the team with a paralyzing (and painful) attack, which he could dial up to a full Agony Beam.
Inverted in Barbarella, Queen of the Galaxy: villain Duran Duran tortures the heroine by hooking her into a device which plays her sexual responses like organ pipes, the goal being to orgasm her to death. Barbarella being Barbarella, it doesn't work.
In The Princess Bride, the "machine" isn't so much a beam as it is a life-sucky thingy, but since it causes intense pain to the victims at various settings, it qualifies as the trope.
Another "life-sucky thingy" is whatever the MCP uses to de-rez (kill) errant programs in TRON. First, we see it used on Clu, then we see Dumont and other elderly (presumably user-interface) programs being put through the same torture.
Kalgan of Space Mutiny has a device he uses to torture the heroine that he claims is modeled on "ancient" dentistry equipment. He shoots a laser at one of her teeth. Doesn't seem to bother her very much, and the laser actually makes the same noise as a dentist's drill.
Genesis II. The mutants have devices that inflict pain by touch. The devices can be set to deliver various level of pain, from a mild correction up to incapacitation.
Played for Laughs in Back to the Future, where Marty, posing as an evil alien, invokes this trope using a Walkman and a Van Halen tape. Surprisingly, the victim didn't notice the headset over his ears, but it's safe to assume he was distracted by the yellow-suited figure threatening to melt his brain.
The neuronic whip in Isaac Asimov's Foundation universe. This leads to a rather warped conversation in Foundation And Earth; while exploring the titular planet, the protagonists are attacked by mutated dogs. Trevize's Disintegrator Ray is almost useless, as the dogs appear to have no survival instincts and continue their assault no matter how many of them die. But when Bliss hits them with the whip, they scatter. As Asimov considered violence to be perverse, even in self-defense, this is something of an Accidental Aesop.
Bliss: With a blaster, Trevize, a dog merely disappears. The rest may be surprised, but not frightened. ...The neuronic whip is different. It inflicts pain, and a dog in pain emits cries of a kind that are well understood by other dogs...
In Dune, the Reverend Mother tests Paul Atreides's humanity with a box that directly stimulates the pain receptors in Paul's hand. She also holds a poisoned needle that will kill him if he withdraws the hand from the box. The logic is that a lesser creature will simply react to the pain and die from the poison, while an intelligent one will be able to override the instinct and save itself. Paul does not know this until he is told to withdraw his hand from the box, however, and what he thinks is happening to his hand is described in gory, most definitely not PG-rated detail.
Another Dune device is mentioned in passing, "pain amplifiers" that presumably make conventional torture that bit more effective with no greater risk of death.
In the miniseries, the box also appears to be transparent and shows his hand searing from the heat. It's actually just a hologram meant to amplify the psychological effect.
Inverted — but oddly horribly — in Larry Niven's Known Space stories with the tasp. The tasp doesn't stimulate pain; it stimulates pleasure, simultaneously being just as incapacitating as pain and threatening a victim with permanent addiction.
In the Known Space book Destiny's Forge, the Patriarch's Telepath projects a void beam: a loss of sensation so horrible you'll beat your brains out on the ground just so you can FEEL SOMETHING. And the Norn's cane in "A World Out Of Time", which inflicts despair on the recipient that makes them want to end their life more than anything in the world. Naturally, it's only used as a torture device when the victim is well restrained.
In Ringworld Engineers, Louis reveals to Chmee that someone once hit him with a tasp. Later, this caused Louis to become a "wirehead", addicted to a wire plugged in his head to stimulate the pleasure centers of the brain.
The Agiel in Terry Goodkind's Sword of Truth series is a magical stick used by the Mord-Sith to inflict pain on anyone it touches. The Agiel also hurts the Mord-Sith if it's the same one she was 'trained' with, but they're conditioned to withstand the pain. It is fatal, however, if it touches anywhere near the heart. There's also Wizard's Pain.
Mord-Sith even use the Agiel during sex. Mistress Denna, the main torturer in the first book, tells the protagonist she has never had intercourse without it.
Sergey Lukyanenko's novel Line of Delirium starts with the main character being killed by an algopistol, a weapon that causes all nerves in his body to simultaneously transmit extreme pain signals to the brain. Normally, the person dies of shock. It is unclear if the main character died from shock or from bleeding out, as his thrashing caused him to cut him his body on some super-thin webbing. He gets better.
The algopistol is specifically referred to as a weapon for losers.
Particularly effective one in Animorphs that also had an opposite number feature built into the device. The idea was, that while pain was a good form of torture, a better method was to cause pain, then an overwhelming happiness, than quickly turn it back to pain to break the victim faster. Rachel considered it's use on Tobias one of the worst things that was done in the war.
Another book described how the Yeerk Dracon Beams were descended from Andalite Shredder weapons, but were altered to cause as much pain as possible. Shredder weapons set to full power vaporize targets almost instantly and painlessly. Dracon Beams set to full vaporize victims slowly enough that they can feel their molecules explode.
Fridge Logic: How did they know that if the weapon itself tears apart molecules? A survivor would be in too much pain to tell the difference between the two anyway...
Presumuably if you hit someone with a Shredder they vaporize instantly, and if you hit someone with a Dracon you can hear them scream for a few seconds.
The agony booth and the agonizer are a feature of Star Trek's "Mirror Universe" first introduced in the TOS episode "Mirror, Mirror." In the Diane Duane novel Dark Mirror, the crew of the Enterprise-D confront their mirror universe counterparts. In the mirror universe, Troi's role as "ship's counselor" involves her using the agony booth a lot and the crew's agonizers take the place of combadges. It's even pointed out how the "old" agonizers were inefficient, brute instruments while the modern version is specifically designed to attack the wearer's most sensitive nerves.
In the Shatnerverse, the mirror Kirk explains how he eliminated his universe's Pavel Chekov after he found out that he had plotted to assassinate him. He threw him into an agony booth, set it at a very low level (he described it as like "a bad toothache, all over your body") and then left him in there for almost two weeks until he died.
The Stainless Steel Rat Goes to Hell features a device called a 'bioclast', used on recalcitrant workers by an evil mine supervisor. Its effect is described by the protagonist/narrator ans feeling "like the flesh had been sliced to the bone and boiling acid poured into the wound".
In the Logan's Run novel, the Sandmen carried a Gun that fired a "Homer", which homed in on the target and, on impact, stimulated every pain nerve in the body before killing the victim. It was the primary deterrent against Runners: If you turn yourself in for Deep Sleep on Lastday, you'll be put to death by pleasurable gas, but if you Run, you'll suffer the Homer.
In Wintersmith, it's shown that very skilled Discworld witches like Granny Weatherwax can take the pain of an ailing patient out of their body and transfer it to somewhere else. I Shall Wear Midnight shows that, if push comes to shove, that somewhere else could be someone else.
Star Wars has a lot of examples of this. In addition to the Force Lightning featured at the top of the page, there are neuronic whips, the nerve disruptor which was a quite literal agony beam, and the scan grid used by Darth Vader on Han Solo and later improved by Imperial Director Ysanne Isard.
In Alastair Reynolds's Revelation Space universe, this is a preferred method of torturing a Conjoiner; since Conjoiners can use their neural implants to block all physical pain, the only way to guarantee that they'll feel pain is by directly communicating it to their brains.
A form of this is used on Winston in the Ministry of Love in 1984.
In Andre Norton's Storm Over Warlock, Shann's first test is being trapped in the memory of a bully using an agony whip on him. Despite the pain of the first blow, he manages to dispel it by remember it was a decade ago and the man is dead now.
Mystery Science Theater 3000 spoofed this with Dr. Forrester's DEEEEEEEEP HUUUUUUUURTING, which he used to keep Joel/Mike and the bots in line. The exact nature of Deep Hurting changed from episode to episode; sometimes the Hurting seemed to be actual physical pain caused by a device, but sometimes it was simply the fact that our heroes had to sit through yet another awful movie.
In The Movie, Dr. Forrester demands that Mike and the 'Bots bow to him. Then he turns and pulls a lever when they don't immediately obey. Whatever happens next, it appears to hurt the 'Bots, too.
Also in episode #611, Last of the Wild Horses, Tom and Gypsy are thrust into the Mirror Universe where Mike and Crow torment Frank and Dr. F. Crow screws something up, but has failed to keep the batteries in his personal agonizer charged and the Agony Booth is on the fritz — again!
The "Brain Guys" were able to inflict pain using their minds to force Pearl and Professor Bobo to fight to the death. For some reason it did not seem to work on Mike or the Bots.
In Stargate SG-1, the Goa'uld "hand device" has this a standard feature. The area it affects is notably red for awhile afterward. Naturally, they love to use it at every opportunity and SG-1 have been zapped so often they should all have a permanent sunburn. Especially Daniel, who in one later season episode quips, "I think I'm starting to get used to that," after it happens once again. It can kill, though, with prolonged use — this just doesn't happen, to the heroes, very often.
At first, one shot of the Zat gun was an Agony Beam, but it eventually became "phasers on stun."
The Goa'uld have another Agony Beam that looks like a cattle prod. When its used, an orange light comes out of the victim's eyes and mouth, and presumably nose and ears (but that's harder to see). O'Neill gets this one used on him a lot.
In an alternate universe, the US is under martial law after revealing the existence of the stargate has caused mass rioting, so the Secret Service is now using the "cattle prod" as a standard tool.
Interestingly, the Agony Booth didn't exactly make the Cold-Blooded Torture any less disturbing to watch. When Star Trek: Enterprise revisited the Mirror Universe in the "In A Mirror, Darkly" prequel episodes, showing among other things the invention of the booth's first prototype and its earliest usage, a lot of the filming crew got seriously upset while shooting the scene in which Mirror Tucker pleads his innocence while Mirror Archer tries to torture a confession out of him using the booth.
In "Dagger of the Mind", there is a Mind Rape machine that looks like a sun lamp shining on a hair-salon chair. And Kirk isn't even strapped in. He could just stand up and walk off, but apparently it's so intense that he only sit there writhing in pain as a sort of post-hypnotic suggestion is used on him.
The Eymorgs' pain bracelets in "Spock's Brain". The unbelievable acting done in this episode would be spoofed many times, most notably in The Wonder Years.
The pain implants used by the mercenaries on Picard and Riker in the two-part episode Gambit.
Also, the pain implants used by the Cardassian interrogator on Picard in "Chain of Command" (The One With the four/five lights argument). The writer, Frank Abatemarco, consulted Amnesty International on the psychology of torturers and their victims, and the actor Patrick Stewart studied tapes from AI in preparing for the scenes. Notably, this one has no sound or light effect to tell the audience when to flinch, just really good acting.
Klingon Pain Sticks, from several TNG episodes. It turns out that as cruel as Klingons can be, they actually need their pain (quote from Star Trek V notwithstanding) from time to time, particularly for important warrior rites.
TOS Klingons used an agonizer as well in "Day of the Dove," and in "The Gamesters of Triskelion" collars of obedience were collars used to keep the thralls of Triskelion in place.
The Star Trek: The Next Generation episode "Allegiance" also had a green ray effect that did this. Certainly a good example of how simple the effects need to be.
In "Power Play", the heroes use a plasma beam to inflict pain on three crewmembers who have been possessed by aliens - not as a means of torture, but to get the aliens to leave.
Then there was the energy field the space jellyfish in Encounter at Farpoint subjects Groppler Zorn to, though the sounds he was making made it sound more like he was in a tickle ray.
In the Star Trek: Voyager episode "Future's End", Henry Starling kidnaps the Emergency Medical Hologram so he cxan torture hi for information. Starling reprograms the Doctor so that, using a remote control, Starling can cause the Doctor to feel as though he is on fire.
The imprinting chairs in Dollhouse can be used to generate this effect, as Bennett shows rather graphically to Echo.
Gene Roddenberry's TV movie Genesis II featured the evil mutant Tyranians using "stims" — short rods which could be adjusted to induce either pain or pleasure on contact. Unsurprisingly, hero Dylan Hunt (the one that one was named for) didn't fall to the ground until the highest pain setting was used. Then they gave him a pleasure dose: carrot after stick.
Subverted in Farscape: the Scarran's natural agony beam is one of solid heat. Not only can it kill, but the camera tends to linger on shots of the victim's skin bubbling and burning as they die- case in point, Prince Clavor and Diagnosan Tocot.
Which shows the power the Ancients have when the Scarran Emperor Staleek tries to mind-probe "Einstein", only for the latter to No Sell the beam with a literal Hand Wave.
Used in the Doctor Who serial "Vengeance On Varos", which leads to the odd spectacle of a shirtless Jason Connery being tortured by having a torch shined on his chest.
Also used / threatened in "Genesis of the Daleks" by Davros against the Doctor / Harry and Sarah Jane.
...and then, there's the Mind Probe. ("What? No NOT the mind PROBE!")
The Teselecta in "Let's Kill Hitler" punished historical criminals by intercepting them at the end of their lives to "give them hell." The beam was used on River Song, but the Doctor intervened so it is unclear whether the ultimate function would have included death as well as pain.
Henry van Statten's body scanner has this effect on the Doctor (with a direct visual Call Back to the torture scene in "Vengeance on Varos"). It's not clear if that's a standard side effect or merely due to van Statten not understanding the Imported Alien Phlebotinum.
Angels of Supernatural have this power, though it's explained that when they make a human double over in agony, it's specifically because the angel is messing with the human's internal workings (breaking their bones, removing their lungs, giving them stage 4 stomach cancer) in a nasty way.
The music video for Powerman 5000's When Worlds Collide has a pastiche of Ming with two agony beam rings, the hero manages to overpower his beams with his own energy blast, disintegrating him.
There are several lines of spells in D&D that do this. The Nybor's line of spells (going from Gentle Reminder to Wrathful Castigation) being particular favourites. 3.x also had an Always Chaotic Evil version named Wrack.
The big daddy of all these spells would have to be Eternity of Torture, which fills the target with unbearable agony unto them being unable to do anything besides writhe in pain. And it makes them immortal. So they can suffer forever.
The not so subtly named Power Word: Pain.
Not to mention Love's Agony from the Book of Vile Darkness. To add to the torture, it doesn't even harm the person it hits, instead harming the person they care for most, making it a spell reserved almost exclusively for being pointlessly cruel.
The Dark Eldar of Warhammer40000 have a literal Agony Beam, as in a weapon that fires pain, for both battlefield andrecreational use. They also have a disturbingly large number of weapons designed specifically to cause as much suffering in their unfortunate victims as possible. They're justlike that.
GURPS: Magic has "Pain" and the much worse "Agonize" (turns every sensation into extreme pain). Ultratech has Sonic Nauseators (pain and loss of bowel control) as well as the Neural Disruptors.
World of Warcraft has at least two spells whose names imply that they do this. Priests have Shadow Word: Pain and Warlocks have Curse of Agony. Both of these spells inflict continuous shadow-elemental damage over a period of time and can kill their targets.
Priest's Mind Flay and Mind Sear probably also count (maybe Warlock's Drain Soul too). All are channeled spells that project a beam that rends the target's mind or souls, dealing shadow damage.
A quest in the Borean Tundra has you use one on a captured mage. The tooltip states that it 'inflicts incredible pain to the target, but does no permanent damage'. After the quest, you can get more of these, free of charge, just for fun.
Several mobs in the game have a "Pain Spike" ability, which inflicts instant damage on a target, but that damage wears off over time.
In Dissidia: Final Fantasy, Final Fantasy II's Emperor Mateus has one of these as part of his EX Burst. Perform it perfectly, and he performs Entice, suspending the enemy in zero gravity as he continually blasts them with arc lighting from his hand, Emperor Palpatine style.
At one point in Lost Odyssey, the Big Bad seems to do this to you—he gets tired of fighting you and uses a spell called "Pain Surge," dealing max damage to everyone in your party. Judging by the following cutscene, it also sends you into a coma.
The Shivering Isles expansion to The Elder Scrolls IV: Oblivion has a quest where you use this. Getting true answers from some people requires several uses.
Star Control II has the Excruciator, a device designed to directly stimulate the pain receptors of an Ur-Quan's brain. Unusual in that it was developed by the Ur-Quan, not for punishment or torture, but to protect against mind control by another species which had enslaved them, and was forced to break their control whenever their victims experienced extreme pain.
Before the Excruciator, they were forced to do things like poisoning themselves (as their hero Kzer-Za did in order to inform the rest of his race about their masters' weakness) and mutilating themselves. Causing pain without lasting damage is probably better.
In Rise of Legends, this is an ability for one of the Vinci hero units, which can be used to immobilize and damage a single target.
Mundus can unleash these in Devil May Cry. He uses them to execute failed minions, like Griffon, and occasionally builds them into his creations, like Trish.
In Dragon Age: Origins, Uldred and his fellow Abominations torture mages with this until they agree to become Abominations themselves.
Is Sid Meier's Alpha Centauri, there's nerve stapling, and its direct application, the Punishment Sphere which consists in injecting pain directly into the nervous system through implants. It is a fate so horrifying to be sentenced to that if you build one in a city, there won't be any riots there anymore. The downside is halving the research rate in that city. The faction leaders also have some reserved for their rivals, when they capture any.
It is not uncommon to see patients undergo permanent psychological trauma in the presence of the Sphere, before the nerve stapler has even been strapped into position. Its effect on the general consciousness of the culture is profound: husbands have seen wives go inside, and mothers their children. Dr. Xynan left the surface of the sphere semitranslucent for a reason. You can hear them in there; you can see them. It is a thing of terrible beauty.
— Baron Klim, The Music of the Spheres
It also works on the Progenitors in the Alien Crossfire expansion, which means their nervous system is, at least, remotely similar to that of humans.
This is the schtick that Saul Karath uses against you in Knights of the Old Republic. The Jerk Ass ups the ante by torturing your love interest if you give him an answer he doesn't want to hear. It's especially brutal if you're playing female considering the long, nasty history between Carth and Saul.
Wild9 puts you in control of one of these. The Agony Beam doubles as a sort of electro-lasso and allows you to throw your enemies off cliffs, slam them into solid objects, shove them through shredders, drop them into jet engines...the list goes on and on and on.
Postal 2 gives you one in the form of the "Shock Rocket" stun gun which, when applied to a subject, causes them to twitch involuntarily and smoke, and then drop to the ground, still twitching, losing bladder control, and whimpering pleas like "Just finish it!" or "I can't feel my legs!" Combine the max-ammo cheat (which bumps the charge capacity up to 999, with usage consuming about 5 units per second) with the fact that the game already runs on Video Game Cruelty Potential, and you can pretty easily see the kinds of horrible (or awesome, depending on your perspective) places this can go.
With the AWP expansion pack, you can also get a modified Shock Rocket called simply "The Puker." Exactly What It Says on the Tin, it induces immediate and incapacitating vomiting with even a split second's application to a subject of your choice.
In the Mass Effect series, the recurring power 'Neural Shock' overwhelms an organic target's nervous system with pain, immobilizing them and causing significant damage. In 3, Mordin zaps an STG agent with it to convince him to break protocol.
In one episode, Bubbles is trying to prove that she's as hardcore as the other Powerpuffs— and takes Mojo Jojo's Agony Device up on its eleventh setting.
Later shows up in the Musical EpisodeSee Me, Feel Me, Gnomey where Gnomey uses a Force Lighting like attack accompanied by Ominous Latin Chanting to eliminate the villains of Townsville as well as take away the girls' powers. When the girls regain their powers and fight Gnomey, he tries it again, though it only serves to stun them for a moment.
In the series finale of Justice League Unlimited, Darkseid gets a chance to show off the "Agony Matrix", which... well, read the quote up above. Ow.
Darkseid's first appearance in Superman: The Animated Series used his Omega Beams on low settings as his greeting to Supes. He had to turn it up a bit to force Superman to kneel though. What makes this just a little bit epic is that this is his introduction. Darkseid is not attacking Superman or trying to kill him, Superman has simply asked who he is. After leaving Superman in a crumpled heap on the floor, Darkseid walks off, looks over his shoulder, and responds "Thatis who I am."
Vlad Plasmius has one of these as a standard ghost ability. Danny is rather unappreciative.
In "Kindred Spirits", Vlad plugs Danny into a nasty-looking zappy capsule thing to try to force him to morph into his ghost form. It even has a dial to increase the intensity! Once again, Danny doesn't appreciate this.
There's a real life weapon being tested as we speak called the Active Denial System. It uses millimeter wave radio energy to heat the surface layer of the skin, causing intense, incapacitating pain with no lasting injury. It's intended for use as a humane crowd control device (especially compared to the alternatives: tear gas, bullets, flamethrowers...).
There also seems to be a possibility that this system may come into actual use soon. Though the system appears to have taken on a more user-friendly acronym (Assault Intervention Device or AID), its function remains marginally unchanged. http://news.yahoo.com/s/ap/us_jail_ray_gun
Serious controversy has been raised over the question of what happens when people are too tightly packed to move, or rendered immobile by injury (Both are likely scenarios in riots and firefights), especially since the long-term effects are largely unknown, but probably not good.
It has been demonstrated to cause burns in skin and if the eye were exposed the cornea would quickly cook causing blindness.
All demonstrations shown so far, the pain has failed to incapacitate; it's hard to resist, but not impossible for a determined person. The same is also true of pepper spray and tear gas.
One occasional myth that does pop up is that metal objects worn by a target can heat up faster and cause more serious contact burns. Metal items are reflective in the microwave spectrum and sheet metal could be used as a shield.
The Long Range Acoustic Device AKA the Sonic Cannon is a sound-based weapon that serves a similar purpose. This is the device that was first widely publicized when it was used to avert a pirate attack. You just can't make this stuff up! (In practice, it "fires" a blast of sound that, without proper protection, screws up the body's balance mechanism and inflicts some pretty serious pain.) What is interesting is that the sound is perfectly directional. The device can be set to fire out at a specific angle from the speakers. For example, if the device projected at a cone of 30 degrees, only anyone inside that cone would be affected. Anyone standing behind it would hear the device working, but the sound level they hear is only slightly louder than normal speaking volume. Anyone standing even 1 degree outside of the cone would hear the same level, but if they move even one degree into the cone, then the pain begins.
To its credit, the device is designed with a less-intense setting, making it a stronger, more precise version of a bullhorn that lets you give, say, an advancing mob, fair warning to turn around before they get the full blast.
Then there's pepper-spray, which, when dispensed from riot-control guns (also used to ward off bears) count as something between Agony Beams and Stun Guns, having a slightly shorter effective range but better takedown statistics than handguns.
Skunks spray victims and predators in an attempt to escape, causing either irritation or even agony. Skunk spray can be let out as either a gaseous mist, or a liquid stream. The mist is very potent and can be smelled from half a mile away. The stench can cause great disgust from a mere 50 ft, and the smell clings to its victim with greater intensity depending on how long it takes for the victim to wash it off. It clings with even greater intensity to fabric or animal fur. The liquid stream, however, is twice as strong and potent, and can be smelled from over a mile away. Being sprayed by the liquid stream can put the victim in intense agony and literally stun them, especially if it is near the face (which can cause temporary blindness).
The active components in Skunk spray have been released to the public in recent years as a toothpaste-like gel. Already, some police services use the potent smelling gel to keep people and animals out of abandoned buildings. It's proven almost 100% effective.
Another US DARPA project, the Pulsed Energy Projectile, used a "low" power pulsed laser beam to vaporize a small portion of the target's surface, causing a small explosion capable of knocking the target down. One side effect noticed in testing was that the EMP generated by the plasma that the laser impact produced stimulated pain receptors, and work was underway to amplify this effect.
Happily, like the ADS system above, the US DoD is keen to distance itself from accusations of torture and devices that might facilitate it, so these projects aren't likely to be released into use any time soon.
Less happily, this effect is something that could be replicated by any real-life laser weapon set to low-power single pulse output (the PEP was effectively a low power version of a Pulsed Impulse Kill Laser project, which did Exactly What It Says on the Tin). In the future, "phasers on stun" won't leave someone quietly snoozing, but burnt and screaming. Lovely.
...and the acronym lends itself to dismissive terminology for the newly "pickled" victim.
A taser can be used to deliberately inflict pain, when operated in "drive stun" mode.
There is also a specialized LED device which projects a beam of light that rapidly pulses random colors. Looking at the light for too long messes up your brain since your eyes can't effectively focus on the colors and then you're incapacitated from a number of nasty side effects, like cluster headaches, nausea, vomiting, disorientation, irritability, and visual impairment. The Secret Service has contemplated using this to protect the President. For example, if the motorcade is traveling down a street, and the SS are tipped off that an assailant will strike from a specific direction, all they have to do is point the device in that direction and EVERYONE over 5 miles will be blinded, friend or foe alike. It's designed to be inconvenient rather than outright painful. The lights aren't so bright as to intentionally cause blindness. It's just that everything suddenly turns completely green.
The device, called a "dazzler", is in active use in situations where it benefits to briefly delay someone. They're sometimes used at checkpoints to discourage suicide dashes, and some prisons use them against uncooperative inmates or to quell prison riots (the idea is to startle them just long enough for the guards to reach and subdue the prisoner(s)).
While not in a beam form, the stings of many small insects (as well as platypuses) are made specifically for causing pain.
The worst example is probably the Irukandji Jellyfish, a relative of the Box Jellyfish. While their stings don't kill unless you don't get help (Box Jellyfish stings are more dangerous, though not by much), they cause such a drastic assault on one's pain nerves that even people in a medically induced coma still scream in pain.