The "anti-hero" comes to science fiction from a variety of sources, including noir and Westerns... but she also has her own uniquely science fictional avatars, that spring out of science fiction's tradition of skepticism and social criticism. The anti-hero is where science fiction's pulpy roots meet its most intellectual aspirations. Plus, he/she totally rocks on ice.

Noir:

My favorite noir hero is Dashiell Hammett's nameless Continental Op, who spends more time orchestrating convenient murders than he does investigating crimes. In the novel Red Harvest, the Op arrives in a town called Poisonville which is run by organized crime, and he systematically tricks the town's ruling gangsters into killing each other, first a few at a time and eventually in a full-on massacre. By the end, he's one of the few people left standing. In noir, nobody's morally pure.

The classic science fiction noir movie is Blade Runner, featuring Harrison Ford's hardboiled and conflicted cop, who's hunting the Replicants without being sure if he's doing the right thing. And of course Blade Runner is based on a Philip K. Dick's Do Androids Dream Of Electric Sheep?, and a lot of Dick's best work has a particularly noir flavor of pulpiness. Dick's protagonists are never sure if they're doing the right thing, and often are just out for themselves. That could be one reason why Dick is the author of choice for movie adaptations — his work is very close to a genre that movie people understand.

Another great science fiction noir author is Richard K. Morgan (no clue if the middle initial "K" is a requirement), whose first novel Altered Carbon is like a fusion of Chandler with Doctorow's Down And Out In The Magic Kingdom: hard-as-nails gumshoe Takeshi Lev Kovacs dies in a shootout, and then is restored from a backup and "resleeved" in a new body so he can investigate the murder of a rich guy (who's also been restored and "resleeved.") And then Kovacs promptly sleeps with the rich guy's wife.

And then of course, there's always Jim diGriz, hero of the Stainless Steel Rat novels, who starts out as an amoral trickster — before eventually devolving into a bit of a pussycat. And there's Gully Foyle, dubious hero of Alfred Bester's The Stars My Destination. (And Alfred Bester becomes the name of a morally gray psy-corps agent on Babylon 5, who becomes more of a sympathetic anti-hero in Gregory Keyes' novels.)

Westerns:

The archetypal Western anti-hero is out for himself, and only incidentally ends up helping others. Often, he (and it's usually a "he," except for Sharon Stone in Sam Raimi's underrated The Quick And The Dead) is only a "good guy" in comparison to the really really shitty bad guys. Think Clint Eastwood's Man With No Name from the spaghetti westerns. Cowboy-influenced anti-heroes in science fiction are usually pretty easy to spot: Han Solo in Star Wars and Mal in Firefly have everything except the Ennio Morricone whistle/trumpet score playing in the background.

I'm also going to peg Vin Diesel's Riddick from Pitch Black as a Western-style anti-hero — he's basically a convicted murderer being transported across the prairie in a wagon train, and then the wagons break down. Will he help save his captors, or let the elements and the hostile natives take care of them?

The Mad Scientist:

Unlike the noir and Western anti-heroes, the mad scientist has always belonged to science fiction, as far back as Frankenstein and Dr. Jekyll And Mr. Hyde. As the name implies, the mad scientist doesn't always have the greatest grip on reality, unleashing forces he cannot blah blah blah. The mad scientist is often just a foil for the hero in space opera and action-adventure stories — but he's also a protagonist a surprising amount of the time.

On TV, Doctor Who features a mad-scientist archetype as the hero, and the early episodes of the series in the 1960s made a conscious effort to portray the Doctor as an anti-hero rather than a more uncomplicated good guy. Over time, the Doctor became purer and more motivated by compassion for other sentients, but he still gravitates back to the anti-hero side of the fence occasionally, most notably in the late 1980s.

Cyberpunk:

Cyberpunk obviously borrowed a lot of themes and styles from noir, but also brought in its own flavor of anti-authoritarianism. The e-zine Computer Underground Digest debated, in 1991, just how anti-heroic the cyberpunk hero actually is. Brad Hicks wrote:

A cyberpunk is to hackers/phreaks/crackers/crashers what a terrorist is to a serial killer; someone who insists that their crimes are in the public interest and for the common good, a computerized "freedom fighter" if you will.

In the works of Bruce Sterling, William Gibson, and others, cyberpunks are not terrorists in the conventional sense of the term, and the analogy to serial killers strikes me as a bit extreme. Cyberpunks are characterized by their resistance to oppressive authority (which makes them a form of freedom fighter), but the resistance tends to be highly individualistic. I wonder if cyberpunks might be based on the anti-hero model of westerns (Shane) or earlier science fiction in which the marginal but basically decent outsider steps in to use marginal skills to save the town, country, or civilization?

The rationalist skeptic, who critiques everyone else's ideals and delusions, is an outgrowth of the mad scientist, and usually has some scientific knowledge. But he's also a nihilistic superhero, who questions human-made belief structures. Avon from Blake's 7 is a bit of a mad scientist and a noir gun for hire, but he's also something else — a foil for rebel leader Blake's idealism who grows into a self-hating amoral hero in his own right. Avon serves as a role model for Horza, the bitter mercenary in Iain M. Banks' Consider Phlebas, the first Culture novel. The shape-shifting Horza tricks a shipfull of pirates into helping him track down a lost Culture Mind in the middle of a warzone. He's willing to make deals with his worst enemies and double-cross his friends, if the job requires it.

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• Deckard's hand-cannon in Blade Runner: Deckard's gun was an amalgam of several other guns, namely the .44 Bulldog and a Styer Model SL. For the movie, they added some winky-blinky lights and a massive grip, making the thing look like it came off of a tank. And who could forget those massive CHOOMPF sounds it made when Harrison Ford fired it? This wasn't a little popgun, it had some real kick to it. It certainly wouldn't be very comfortable to wear in a holster under your coat, but it would give you some serious intimidation skills when you whipped it out.
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• The Good Samaritan Gun from Hellboy: Not to be outdone by Deckard's overly large firearm Hellboy sports a truly massive revolver that would dwarf a normal hand. According to the comic books, "The gun itself has unearthly resistance to almost all forms of attack, and includes grips carved from fragments of the True Cross. The metal of the gun is forged from a combination of Irish church bells, cold iron from crucifixes, blessed silver, and other mystic metals." Plus it comes with a handy lanyard so he doesn't lose it. Of course, even that gets dwarfed in Hellboy 2: The Golden Army when he whips out another gun called, no lie, The Big Baby.
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• The M41A Pulse Rifle from Aliens: While Ripley used to be a blue collar salvage worker, she proves that she wants to fight alongside the Marines in Aliens when she asks Kyle Reese... er, Corporal Dwayne Hicks to show her how to use this gun. It's basically a balls-out automatic rifle, complete with an underslung grenade launcher. She gets through the lesson and quickly becomes an expert in popping caps in Aliens. This supposedly also inspired the Assault Rifle in the Halo series, so it's definitely something to have on-hand during alien invasions.
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• The Varon-T Disruptor on Star Trek: One episode of The Next Generation called "The Most Toys," obsessive collector Kivas "Douchebag" Fajo had four of the five of these highly illegal, outlawed collectible guns. They could tear your body apart from the inside, in a slow and painful manner, which is why the Federation outlawed them. Of course, it was still fine for Worf to carry around a bat'leth sword. That couldn't be painful at all, could it?
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• The Lasseter Laser Pistol on Firefly: Not to be outdone by Trek, Firefly later had their own ultra-rare gun (the prototype handheld laser pistol_ and it was named after the jovial and affable John Lasseter of Pixar, who directed Toy Story... which Joss Whedon helped write. Mal and his on-again, off-again "wife" Saffron conspired to steal this sucker and make some dough, but things never really go as planned on that show.
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• Reason version 1.0B7 from Snow Crash: In Neal Stephenson's cyberpunk novel Reason is a gun that comes complete with its own operating system, carrying case, and a heat exchanger that you need to drop into a nearby body of water to keep the gun from overheating. It fires spent uranium rounds gatling-gun style, and features millimeter-wave radar, giving you daylight vision, even during the night. It might not be the easiest thing to carry around, but it's deadlier than the bubonic plague. As long as the system doesn't crash.
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• The Needler gun from the A Stainless Steel Rat novels: Harry Harrison's Rat books still haven't been adapted for film or tv, which continues to vex us. It's a great property that needs someone smart to bring it to the screen, big or small. Needlers, or needle guns, are popular in the series, and can be outfitted with different types of needles: tranquilizer, paralyzer, nerve toxin, truth serum, etc. Anyhow who is already scared of needles certainly wouldn't like this thing. If you haven't read these, A Stainless Steel Rat Is Born is a great starting point.
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• The Sandman guns from Logan's Run: In the movie, the Sandmen fired guns with an incendiary charge at the Runners. Deadly, yes, but not too imaginative. However, in the books they were six-round guns, and each round did something different, like the "homer" bullet which tracked you and would burn out every nerve in your body, or the "tangler" shot with was a sticky, goo-like web substance. Always be prepared!
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• The Lawgiver from Judge Dredd: Since a Judge was judge, jury, and executioner, this thing came in handy. They were DNA locked to each individual Judge, and featured bonus items like heat-seeking bullets, rubber "ricochet" shots, armor-piercing rounds, and even grenade rounds. Oh, and it also had a top range of three miles (!). That's some serious distance. Of course, if your bullet is going to explode when it hits, maybe aiming isn't that important at that range. Plus it gives you the ability to shout "I AM THE LAW" whenever you want.
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• The thermal smart bullet in Runaway: Granted, Gene Simmons' over-the-top performance in this Tom Selleck action flick from 1984 was pretty lethal. However, all eyes were on the "smart bullet" that Simmons' character had devised. It could be encoded with its targets thermal signature and track them, even around corners. The POV shots of it in flight were flight reminiscent of that flying needle in Dune, but it was cool and scary just the same. And yes, we know it's not a gun, but a bullet. Just remember guns don't kill people... the bullet has a lot to do with it.
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• Soran's gun from Star Trek Generations: While we're loathe to put to Trek entries on this list, Soran's gun gets a special mention for the street cred alone. You know how gangstas like to turn their gats to the side when they hold 'em? Soran's will turn right side up when he "gangsterizes" his hold on the pistol, for no apparent reason. The barrel just sort of flips back upright when he holds it sideways. It might look a bit like a doctor's exam tool, but at least it gives you some props and bling value.
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• The Zorg ZF1 Gun from The Fifth Element: Zorg's gun is nothing short of spectacular. It can break down into four pieces that are undetectable by x-rays, is good for left or right handers, features a 3000 round magazine, has a "Replay" button that sends all shots to the same location, a rocket launcher, an arrow launcher (with posion or explosive-tipped arrows), a net launcher, a flamethrower, and an "ice cube" freezing blast. Oh, and it'll self-destruct if you push the button on the bottom. Not bad. We could go on about it, but it's better if you just watch Zorg himself infomercial-it for you in the video below.
  
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