The Orgasmatron Booth
Maybe I should be more surprised that Woody Allen would come up with one of the most well known pieces of SF sextech in Sleeper, his one and only SF movie to date, but all I can think is that anything that demonstrates how easily people can be replaced by machinery is right up his 1970s comedy neuroses alley. Sure, science may have tried to create the real thing, but the fact remains: Is there a closet that I can walk into and experience multiple climaxes without the presence of another human being and risking repetitive strain injury? No. And that's the true tragedy here.

The Excessive Machine
Unlike the Orgasmatron, Barbarella's Excessive Machine is made for evil purposes, apparently (Unless you think that "Executioner" is some kind of porny euphemism), but you can't deny that with a little reworking, this organ-based organ-replacement could bring happiness to a great many people everywhere, while being more aesthetically-pleasing to look at than any of the inventions seen so far on popular internet destination Fucking Machines (Dear everyone: That link is very NSFW. Do not blame me when you click on it in your place of employment and get in trouble. The clue as to why may be in the name of the site).

Sex Rays Of Various Types
Whether it's Flesh Gordon's Sex Ray or Orgazmo's Orgazmorator, there's no denying that there's something primal about the idea of making that penis/gun substitution a little more literal than usual. The best variation of this idea belongs to 2000AD's satirical Big Dave strip from the 1990s, wherein Saddam Hussein unveiled his plan to defeat the West once and for all by using his Love Gun - built by aliens, of course - to turn opposing armies gay, and therefore - proving the reasoning behind the US military's ban on homosexuals - useless as soldiers.

Freaky Virtual Reality Sex
http://io9.com/5054503/the-dos-and-donts-of-cybersex
Lawnmower Man's face-melty sex scene may look somewhat cheesy now - and make you go "Hey, it's Frank off Lost! But young!" - but let's face it; Second Life really doesn't compare to the virtual reality insect fetish sex that this movie promised us. Science fiction loves to suggest that VR will open up all new worlds of sexual exploration (Even Star Trek: Deep Space Nine had Quark's holodeck suites, which you knew were dens of perversity and characters fantasizing about Dax and Kira getting it on with them), but the reality has proven to be somewhat lacking.

Sexbots In General
I know, I know. Sexbots; they're the android dream for all of us, whether they're Cherry 2000, Battlestar Galactica's Six or any of a large number of other possibilities, there's something amazingly alluring to many people about the idea of a lifelike play partner that only does what you tell it to do (or maybe not). But when I don't care how realistic they think robots are getting, that whole dead-eyed look just doesn't do it for me just yet. Give me a call when they've reached Tricia Helfer level - or maybe Sky-Doll.

Malice@Doll. (2000) Maybe the only philosophical tentacle porn anime movie ever. All the humans are dead, just like in that Conchords song, and the humanoid robots still go about their tasks. Malice@Doll is a sex robot, who wanders the streets looking in vain for human customers. One day, she follows a vision of a girl who seems to be human, and winds up getting captured by a tentacle monster, which penetrates her. A lot. And then she becomes human. She finds that her kiss can turn other robots organic too, but eventually discovers that some of the results are grotesque and horrifying. Sadly, it's not a very sexy movie, but Malice is sorta cute. Here's a still:Cherry 2000 (1987). She's the ultimate sex droid — as long as you don't get her wet. Businessman Sam Treadwell ignores this important lesson and short-circuits his sexbot. So he has to hire E. Johnson (Melanie Griffith), a tracker, to get a replacement memory chip for her. As he travels with E., Treadwell learns (bah) that flesh-and-blood lovers are better than robo-babes.

I.K.U. (2000) Japan's most famous cyberpunk porn movie. Reiko is a shape-changing sex droid from the Genom Corp., who goes around collecting "sexual experiences" by having sex with various people. The corporation collects Reiko's experiences and sells them (in vending machines) as virtual reality chips. But a rival corporation has created its own sex droids to infect Genom's sex droids with a virus, so as to steal their proprietary sexperiences. Dood!

Blade Runner (1982). Daryl Hannah plays Pris, a "basic pleasure model" born on Valentine's Day. She's designed for sex-work in the off-world colonies. She gets retrained as an assassin and uses her amazing acrobatic moves to kick Harrison Ford's ass.

A.I. (2001). Jude Law plays Gigolo Joe, a sex robot who gets framed for the murder of a client. Joe befriends the boy robot David (Haley Joel Osment) and takes him to the ultra-decadent Rouge City in search of the Blue Fairy. And no, that doesn't sound obscene at all. Here's a clip of Jude taking Haley to the decadent metropolis: Circuitry Man (1989). Danner is yet another e-gigolo, a "romeo droid" programmed to provide love and companionship and maybe a little nookie on the side. Danner's programmed to think he's in love, so his female boss can manipulate him into doing her bidding.

Weird Science (1985). This is sort of an edge case. Kelly LeBrock is a sex-bot who manages never to put out. Anthony Michael Hall (playing his usual teenage nerd role) and his friend program a government computer to create a simulation of the perfect woman, and an electrical storm miraculously turns her into a three-dimensional artifact. And then she teaches the boys about life and stuff.

Buffy The Vampire Slayer (1997-2002). When psycho-nerd Warren makes himself a robotic girlfriend, Spike the naughty vampire wants one of his own... except he wants it to be just like Buffy. The resulting bot gets Spike into trouble, but then becomes one of the most valuable members of the Scooby gang. Yet another example of a sex bot who turns into a deadly operative.

Heavy Metal 2000 (2000). A sex robot is programmed to make loud and exaggerated sounds of excitement and climax. She teams up with our heroes to stop the sex lizards. Or something.

Millennium (1989). The John Varley short story and novel include Sherman, a robot who attends to Louise's needs, including her frequent sexual urges. In the 1989 movie, Sherman mostly just provides emotional support to Louise (Cheryl Ladd). (Bah.)

Luckily, he later meets a human chick who protects him from some bad guys and shows him that robot ladies aren't as good as biological ones. I feel like there is some anti-robot prejudice here. If I were choosing between Melanie Griffith and the Cherry 2000, I would totally do that robot.