Social networking's revenue is something that continues to puzzle us all, it is said.

James Drake-Brockman, the show director at Internet World, said that one of the big questions of the internet is just how much such websites make in revenue each year, adding that many are unaware of where such sites make their cash.

He said that aside from the odd behavioural advertising on main pages of these sites, there is usually little people can identify as real advertising and money-spinners.

Mr Drake-Brockman said: "Is it about creating enhanced groups that you can sell as an opportunity to people so they can use it like a micro-social networking site?

"I don't know the answer to it and I think people will be trying to figure it out for themselves."

Facebook, one of these websites, currently has over 200 million active users and half of these will log on to the website every day.

More than half of small businesses (53 per cent) believe that the most important benefit of outsourcing is guaranteed response times for IT support. London-based Connect conducted the research in 2007.