Recent Pixar smash Wall-E imagines a future in which lumpen humans only engage with each other through computer screens. Worryingly, this seems all too plausible a prospect.

Online interaction and social networking are two of this year’s Fringe hot topics. There’s the predictable slew of comedy shows with titles punning on Facebook and MySpace, but, more intriguing are several theatre shows dealing with this static medium. As love, sex and basic human interaction – the lifeblood of drama – are increasingly conducted online, in non-physical worlds, where does this leave live theatre?

Australian actor Ash Flanders, appearing this year in one-man show I Love You, Bro, based on the true story of a suicidal teenager who becomes obsessed with a boy he meets in a chatroom, explains how his company created drama from static interaction. ‘When we decided we wanted to adapt the story, we thought, “How on earth do you translate that to the stage?” Our set’s very minimal – just me, in a hoody, on a computer chair, and we project these basic, colourful, text-based images onto the stage that highlight this pretend fantasy world my character, Johnny, is living in. We didn’t want the audience to just be looking at a pretend computer screen; our design is more abstract than that, with shifting shapes and pixels that remind you that Johnny’s world is not necessarily based in reality.’

Flanders understands the attraction of a make-believe online world. ‘On the web you can be anyone. You can be the wittiest person in the room, you can be the sexiest person in the room, and that’s the currency of I Love You, Bro: it’s pure intellect on the web. The physical just doesn’t matter.’

At the other end of the theatrical spectrum is The Adventures of Butt Boy and Tigger, a comedy about two gay men who use the safety of online anonymity to explore their sexual fantasies.

‘We are all looking for different ways to connect with people,’ says writer/director Steven Dawson (also an Aussie), who came up with the idea for the play after a couple of his friends had tried online cruising sites, with varying degrees of success. ‘Online we decide how we want to paint our pictures and leave the viewer to decide whether they like what they see. It offers freedom. When I finished writing the first scene of the play I was amazed at the vast amount of pornography I had put down on paper!’

The major problem inherent in plays about online relationships is how to convey the action – conducted in text – to an audience. Because Dawson’s characters, Butt Boy (aka Jamie) and Tigger (Matt), engage with the extremities of each others’ fantasies, he decided to exaggerate their movements. As the wild, extreme sex they have exists only in their heads, it actually leads to more outlandish physical action. ‘The physicality of the piece was the easiest part of the process: graphic actions played up to such an extreme level that it becomes very comic,’ says Dawson. ‘Once the characters move away from their desks to play out the scenarios, the play becomes pure X-rated storytelling!’

Adventures of Butt Boy and Tigger, Pleasance Dome, 556 6550, 2–25 Aug (not 12, 19), 10.50pm, £7.50–£8.50 (£6–£7). Previews until 1 Aug, £5; I Love You, Bro, Pleasance Dome, 556 6550, 2–25 Aug (not 12, 19), 2.25pm, £8–£9 (£6.50–£7.50). Previews until 1 Aug, £5.