After charting the history of sex through the ages, we have come to our final destination: the future. But what will sex be like in the decades and centuries to come? Playboy Playmate sex droids? Orgasms at the press of a button? Only time will tell, but until then we can have some fun speculating.

As with all speculation about the future, science fiction is where the action is. From Blade Runner to AI to new Bruce Willis film Surrogates there have been countless explorations into how sexual dynamics would work in a future where emotional humans will increasingly interact with robots. And despite the risks of malfunction and attempts on your life, if the androids look anything like Darryl Hannah's Pris in Blade Runner - a "basic pleasure" replicant whose pleasures look anything but basic - there will be plenty of us who are more than keen to "interact" with these sexbots whatever the dangers.

But if replicants aren't here just yet, they are at least in the post (or more likely on email). Simply browse the internet for "virtual girlfriend" and you will come across (perhaps literally, depending on what you're doing with your other hand) KARI, the most popular of a new breed of virtual chicks who will mimic a real life partner in any number of ways, apart from actually having a physical existence that is. Standing for the positively unsexy Knowledge Acquiring and Response Intelligence, KARI will do anything from holding a civilized conversation with you about your day to talking whatever grade of filth turns you on. Worryingly though – both for those who designed her and those who download her (only $14 folks!) – KARI doesn't look a day over eight years old.

But fears about encouraging cyber geek paedophiles aside, the internet does create some exciting new possibilities for sex in the 21st Century. Whether it be having a mutual wank with your long distance girlfriend over Skype, making use of the dizzying amount of UGC grot available on sites like YouPorn, or marrying a complete stranger in Second Life, the internet will change the way people get turned on and get off in the next hundred years. (Although if we ever invite you to our wedding in Second Life, you have permission to shoot us in the face.) Along with creating opportunities for the socially retarded and the sexually inept, the net also raises questions for the more promiscuous among us. If you meet someone in a chat room, swap some dirty messages and then blow your load on the keyboard, does it count as infidelity? Is your answer the same if it's your girlfriend getting off to another guy's smut?

Back in the physical world, for those looking for a more hands-on (or in this case robotic arm-on) approach, there is the less sophisticated phenomenon of the 'Fucking Machine'. Although only available for women currently (men have to satisfy themselves (manually) while watching, or by resorting to their reliable old inflatable friend), the fucking machines can satisfy a girl from a few feet away. And they are pleasingly simplistic in their approach. Take the Sybian, a sort of vibrator on a saddle, or the Orgasmatron (named after the Woody Allen invention from Sleeper), or the unimaginatively titled 'fucking machine' itself, which pretty much does what it says on the tin: pummeling the girl as she lies back via a dildo strapped to a pneumatic pump. Not exactly rocket science. Slightly more sophisticated, and certainly more portable, are the new breed of “intelligent vibrators”, devices that memorize the patterns of speed and direction that turn a girl on and replicate them time after time.

Away from robotics and virtual intelligence, there will be developments in chemistry and biology. For a different fictional perspective on the future, take Aldous Huxley's groundbreaking 1932 novel Brave New World, a dystopian classic set in London in 2540. Promiscuity is encouraged; in fact monogamy, romance, marriage and family are all considered taboo. Society has developed to an advanced stage where raising infants is too important to be left to individuals and is taken care of by the state. To encourage promiscuity, citizens are given sex hormone chewing gum, not a million miles away from the relatively recent introduction of Viagra.