Snow delays, straitened travel budgets, arbitrary security crackdowns and the knowledge that they will never match George Clooney's air miles in Up in the Air have left more than a few business travellers wondering whether their next trade show trip looks quite so appealing.

The exhibitions business has been one of the corners of the traditional media sector least damaged by digital technology. Even as social networks from LinkedIn to Facebook consume ever more time at their desks, people have not lost sight of the value of pressing the flesh.

Events attendance has always been susceptible to travel interruptions from Sars to terrorist attacks, however, and the downturn has created a new focus on whether costs and travel requirements can be taken out of the equation while preserving the experience of doing business face to face.

The outcome can be seen by visiting the shimmering venue where Information Week, the magazine, recently ran a "dark reading and black hat" event on data security threats. Inside the cavernous exhibition hall, delegates milled round booths, inspecting white papers from exhibitors such as Novell, AT&T and Imperva. Off to one side, contact details were exchanged in a networking lounge while in a darkened auditorium the audience listened to a keynote panel discussion: "Data is valuable: bad guys want it."

But the show was not in London's Olympia or New York's Javits Center but entirely online. The visitors and exhibitors are avatars moving round a virtual environment where booths offer "content racks" of podcasts, business cards are "V-cards" and presentations are webcasts.

The most physical of media forms is going virtual. From a standing start three years ago, some of the industry's biggest global organisers have begun offering hundreds of online-only shows, often using specialist developers such as CGS, InXpo, ON24 and Unisfair.

In 2008, United Business Media ran 15 virtual events, says David Levin, chief executive. Last year, that number increased to 48, and in 2010 he expects to run more than 100 such shows.

Sharat Sharan, chief executive of ON24, estimates that the more than 300 virtual events and 30,000 webcasts it has organised to date are driving 30-40 per cent growth in its annual revenues: "2009 was the first year virtual events really took off," he says.

The data on these early events have impressed industry veterans: the average visitor will spend more than two hours in a virtual event. "This is a tool that's here to stay," Mr Sharan continues. "It's going to have the best of the physical environment and the best of the virtual environment, such as social networking," he enthuses.

If the idea sounds familiar, it may be because similar claims were made for Second Life, the much hyped virtual world that just a few years ago was supposed to become the new meeting place for everybody from warlock-fancying hobbyists to car salesmen on training courses.

But the Second Life experience made many events organisers wary. "We tried that. It was interesting. It was a trial - in that case, an expensive one," says Mike Rusbridge, head of Reed Elsevier's events business.

Mr Levin recalls that UBM's online events experiments began in 2007 with a few "incredibly expensive" events in Second Life for a specialist technology audience. "It cost us more than $1m (€730,000, £660,000) per event, but the good news was we were getting more than 1,000 attendees. We liked the level of engagement but didn't like the complexity of Second Life. It wasn't business-friendly."