Bigbrother.terra.com, the website which broadcasts round the clock surveillance of Channel 4's Big Brother house, was one of the most popular websites in Britain last month and has contributed to a four-fold surge in traffic to the main Channel 4 website .

A report from internet research company MMXI Europe, which tracks 85% of internet traffic worldwide said the site had shot in at number 26 - ahead of many household names including Lastminute.com and Tescodirect.com. Some 8.1% of people with home access to the internet visited the site in July.

The Big Brother website has pivoted the main Channel 4 website to 34th place in the table, ensuring one of its best months to date with a 6.9% reach.

A Channel 4 spokesman said: "We knew it would drive traffic through but it was not the reason for doing it."

He said the station had set no targets for either TV ratings or visits to the web site but was obviously pleased with the outcome.

Paul Munford of Victoria Real, the company which built and manages the Big Brother website, said: "It has surpassed our wildest dreams. The site only went live on July 14th so any figures will be an underestimation."

He said the figures for August would be bigger, especially around the time of Nasty Nick's departure, which was shown live from the site on a video screen in Leicester Square.

Mr Munford said the site would be more than able to cope with any further surges in traffic as the show reaches its climax in the coming weeks.

Bigbrother.terra.com is the only website in the top 30 for a single entertainment vehicle. Just two established media sites, BBC.co.uk and Virgin.net, have made the top 30 taking up numbers 10 and 18 respectively. Top of the table is MSN.com which reached 38.3% of the potential internet audience.