KEY POINTS:
Playground bullies are deploying iPods and social networking sites such as MySpace and MSN Messenger to wage increasingly high-tech campaigns against their victims.
Academics studying the growth in so-called cyber-bullying discovered that youngsters, particularly girls, ruthlessly exploited every new technological gadget and craze.
Victims reported feeling more lonely
in school, having fewer friends and being less liked than their peers.
Among the findings was a growing trend to circulate embarrassing video clips of young people getting changed after school PE sessions.
The images are being captured on mobile phones and passed on to classmates' video iPods.
The clips were accompanied by sound tracks of critical comments from laughing tormentors about their victim's body shape or physical attractiveness.
Others reported finding themselves being abused on their own and other people's MySpace and Bebo sites, although the researchers said operators were quick to remove offensive entries.
There was also evidence that MSN Messenger, a popular freeware messenger service provided by Microsoft, was emerging as a hurtful new weapon.
Disparaging remarks were also being logged on online gaming sites.
The research, presented at the British Psychological Society conference in York, found that 16 per cent of children were victims of cyber-bullying - up by nearly a quarter since 2002.
While the numbers appeared to have levelled off in the last 12 months, partly as a result of increased media coverage of the issue, researchers admitted that children were often ahead of them when it came to finding new ways to get at their victims.
According to Nathalie Noret of York St John University, cyber-bullying is now the second most prevalent form of playground intimidation.
"It seems that as soon as something new comes out - no matter how unlikely it might appear - bullies quickly learn how to use it," she said.
"Bullying in schools is a serious problem and this research demonstrates that technology is supplying new ways of tormenting victims.
"As the levels of cyber bullying are increasing it is important to ensure that current anti-bullying strategies incorporate tactics to tackle this," she added.
The study of 15,000 students at secondary schools in York, found girls were much more likely to be cyber-bullied than boys.
The study found that 20 per cent were affected in 2006, compared with just 10 per cent of their male classmates.
Direct verbal bullying however remained the most prevalent form among both genders.
Ms Noret said girls were encouraged to be less confrontational than boys and so were more prone to turn to "covert forms of aggression".
She said: "Girls are socialised from a young age not to be aggressive and are rarely directly confrontational. Direct bullying is much more of a masculine trait."
The study, which analysed text and email bullying, found mobile phones continued to be a potent weapon in the hands of the bully.
Insults such as "slag, slut, bitch and fat cow" were among the most commonly traded.
After body shape, homophobic insults were the second most common form of abuse.
More worryingly, 5 per cent of text messages raised the prospect of physical violence - not just against the victim but also their family.
Threats such as "we know where you live" proved particularly worrying to some children.
New ways of bullying had also emerged on MSN Messenger, according to Ms Noret.
Victims could find themselves blocked from internet discussion groups while others found their accounts hacked into and insults sent to everyone on their contacts list.
John Carr, of children's charity NCH, said youngsters faced unprecedented new pressures with the advent of new technology.
"Bullying has been around for time immemorial. Before it was possible to go home and close the bedroom door and escape, but in an online environment it is 24/7."
- INDEPENDENT