On the day of Apple’s court victory over the Beatles, the BBC invited new-media expert Guy Kewney to discuss the implications on BBC News 24. Due to a mix-up, another Guy (Goma), an interviewee for an IT job also waiting at reception, ended up miked and on set. Bless him, he mugged his way through the questions, thinking they were part of his interview. When the BBC realised, it apologised on air. Within hours, footage was on www.youtube.com, a site of home-produced videos; within 24 hours, it had been forwarded round the world, with a guesstimate that 100,000 people had seen it by last Monday.

The wonder of the telecoms age, it seems, is that it’s possible to take the mickey on an instant and global scale. Sites such as Youtube, or a basic knowledge of picture-manipulation software like Photoshop, mean that today anyone can be a situationist prankster with little more than a computer and a broadband connection. George W Bush is the internet’s most mocked — in Photoshopped stills of Bushes Sr and Jr proudly holding a freshly caught fish in a flooded New Orleans, mad cut-ups of Dubya’s speeches and stills of the Prez reading an upside-down book or looking through binoculars with the lens cap still on.

With the video-creation site Youtube, established comedic talents such as Robert Popper, Sarah Alexander and Peter Serafinowicz have been using basic technology to spoof dumb E! TV bulletins with O! News. “When we were working on Look Around You, the fake science show for BBC2, we did a lot of stuff online,” Popper explains. “We did little films, and there was a site where we mocked up visions of what 2000 would look like from 1970s science shows. We were really just doing it for fun, and didn’t think these clips would make it into a show. We’re at the point where the net and television are beginning to merge as creative mediums. It’s just that you can get something online quicker and cheaper.”

The audience numbers for a viral can be astonishing. When the comedian Paul Kaye, who pranked celebrities as Dennis Pennis, had a sketch-show pilot rejected by Channel 4, he took his favourite clip and flung it out into the ether. The skit showed a martial-arts tutor delivering his “total concentration” lecture before choosing an opponent and wading into him in full windmilling football-hooligan style. It went online just before the World Cup in 2002. Although the total is probably much greater, the company who put up the Jpeg know for certain that at least 60m people have seen it to date. “During the quiet years, when there wasn’t that much work about, I think it kept me in the public eye,” Kaye says. “I didn’t get a penny for it, of course, but that doesn’t really matter.” He plans to put some of the more risqué skits from his new MTV show, Strutter, online as virals after MTV deemed them too edgy.

Virals have grown into such a cultural force that the Institute of Contemporary Arts (ICA) in London ran an exhibition of the finest earlier this month. It was like a greatest-hits of the internet, with Tom Cruise jumping around on Oprah’s sofa, talking cats, farts during The Matrix, George Lucas spoofs and the infamous Sex Olympics, in which Eastern European contestants had to perform a saucy high jump, landing between a woman’s thighs. “We had the show to identify what we saw as a new cultural form,” explains Ekow Eshun, the ICA’s artistic director. “I wouldn’t go so far as to call them art.

They remind me of the satirical cartoons of the 18th and 19th centuries. I like the way they’re raw, unfinished, offensive, shocking and funny. In an age when computers are leading to more surveillance, this is how people are responding, using the computer to mock the world we live in.”

Of course, the irony is that virals or download spoofs are among the most surveyable forms of communication around. Each time a chunk of QuickTime video is passed from computer to computer, it can send back a “sprite”, a chunk of information telling the person who created the content that someone has seen it, and where they are. Hence the ad industry’s interest. The Sex Olympics, for example, was actually an ad for Trojan condoms. It is estimated that adland spent $2.6 billion online in 2005.

Jez Jowett, of the marketing agency Cake, estimates that about 10% of that is spent on virals. “They’re incredibly cheap and efficient,” he explains. “They cost a fraction of the cost of a TV ad, and you can seed them, spread them around. With sprites tracking the content, it’s a more accurate way to measure than any other media offer.”

Thus, Sony recently set up a website inviting consumers to make ads for the brand; Coca-Cola has a video of Jack White’s Coke anthem jumping in and out of in-trays; and Budweiser is all over the web. “Virals are starting to reach overkill,” says Rana Reeves, of Jackie Cooper PR. “People are deleting half the stuff in their inbox before they even open it. We now want to seed social networks like chat rooms, offer a good bit of content and use it to get people to register on a site to download it voluntarily.” Which is all very well if you’re winning the culture war with online pranksters. If you’re the BBC, however, there are some uses of your logo you don’t want people to see. Guy Kewney, anyone?