A UK start-up company on Thursday launches the latest scheme to get Web surfers' attention - Internet software that pays users upwards of 25p an hour to stay online.

Sharkhunt.com hopes to mimic the success of AllAdvantage.com, the American Website that claims to have created the fastest-growing community in Internet history with a similar scheme.

The idea is that Sharkhunt members will download software that installs a bar along the bottom of their browser showing adverts. The ads will change every 20 seconds and as long as it is up on the screen (it takes up about 10% of screen space), users will earn 25p per hour of time online.

What's the catch?

If they refer another user to Sharkhunt they receive 10p for every hour that they spend online and another 5p for someone referred by the second user, and third user and fourth user, meaning an extra 25p an hour in total could be earned from referring a friend.

In theory, office workers, just by keeping their computers on 24 hours a day and referring nine colleagues doing the same and making referrals to the fourth level, could be earning up to £2.50 an hour, or £60 a day or £1800 a month each through the scheme.

So there has to be a catch ... or several:

• Sharkhunt will initially limit payouts to £20 per month until it is sure of its business model. It will probably not pay out before £75 in usage have been accumulated, and users will be given the option of taking Sharkpoints instead, to buy goods online.

• Although it expects 500,000 people to sign up in its first six months, it will stagger the release of the ad bar software. UK users accessing the Net from home will be given preference initially.

• Users have to supply name, postcode and age and the sites they visit are monitored with their traffic passing through Sharkhunt's servers. The company says this should not slow performance and confidentiality will be respected. Advertisers will be presented with aggregated data about users with personal details separated out.

• Sharkhunt is working on "security measures" to ensure the ads are watched. For instance, it says it may be able to tell if there has not been any mouse movement over a period of time, indicating no-one is at the computer.

'Everyone's a winner'

The site is open for registrations from Thursday and the ad bar will be distributed in the next two to three months. It should include an e-commerce channel as well as the banner ads.

The company says it is in talks with DoubleClick and 24/7 Media about outsourcing ad sales initially.

Zia Uddin: Next generation

Its founder, Zia Uddin, a former investment banker with Deutsche Bank, says everyone is a winner with the scheme: users get paid, advertisers get valuable feedback and the company can charge higher rates for that privilege.

"This is the first of its kind in Europe so we have a massive advantage, This is nothing like the free ISP [Internet Service Provider] revolution, we are the next generation," he says.

In the US, AllAdvantage says it has accumulated 1.8 million members in its first 100 days and is now the 38th most visited Website on the Net.