When Brent Hoberman sold his Lastminute.com shares in 2005 for a reported £26.4m, the old Etonian could have taken himself and Genevieve, his Belgian wife, off to a Caribbean island to live happily ever after. Or at least enjoyed a smug retirement, knowing that he and the company’s co-founder, Martha Lane Fox, changed the face of internet retail for ever.

But that’s not what competitive, ambitious dotcom millionaires do. The father of two is still driven by the possibilities of the internet. “I’ve always thought you become a sad old bastard when you start thinking about what you have done. The future is more interesting,” he has said.

And so he has just launched Mydeco.com, which began when he was decorating his Kensington house with Genevieve, who is an interior designer. “She’d give me drawings and swatches of fabric and ask, ‘Should we have this chair or that one?’ ” says the self-confessed interiors Luddite. “And I’d have no idea. I couldn’t visualise the chair. I couldn’t picture what it would be like in the room. I didn’t know whether it would go with the paint. And I didn’t like not being able to make a decision.”

Being Hoberman (the grandson of a man who turned a single South African shop into a chain of 650), he wanted to find a solution. And so he drafted in Lane Fox and John Hitchcox (from the designer-architect firm Yoo) to be on the board, with the former eBay honcho, David Kelly, as CEO.

Mydeco.com is one of the most innovative ideas the design world has seen in recent years: with every retailer from Argos to Marks & Spencer, John Lewis to The Conran Shop, signed up, it is a mix of online retailer, social networking site and slick magazine. A site that, rather cunningly, encourages consumers to spend, socialise and play house at the same time. It is interiors porn to indulge in at your desk.

“There are a lot of men and women like me who can’t visualise, but this should give them confidence in their style,” says Hoberman, explaining how his wife (who isn’t as computer-savvy as he is) has just snapped up chairs for their two toddlers’ rooms online. “And once you feel that confidence, it’s easier to buy.”

The site has a 3-D space function that allows users to plot the coordinates of their room and drop in products from any of the site’s 500 retailers. Then, with a click, they can buy every piece they want – it’s the same price as on the high street, but all under one roof. And being online, that roof is your own.

Obviously, as one of the few entrepreneurs who survived the last burst of the internet bubble, he knows there is a lot at stake. “The market is worth £14 billion,” says Hoberman. “So even if we get a small share of it, we’ll do well.” Income is derived from advertising – though, thankfully, no pop-ups – and for each sale made, Mydeco.com takes a modest cut.

Like any big project, it hasn’t been without its hitches. The original launch date was last September, and there are still a few technical issues to be sorted: photographic quality is patchy, and you can’t yet buy every single thing in every model room.

But this is just the start. “I want people to be able to send an e-mail saying, ‘We have a white sofa at home that looks amazing, but you can’t wipe it down,’ and for somebody else to e-mail back with suggestions,” Hoberman says.

So, has all this cushion-arranging changed Hoberman’s taste? “Not likely,” he says. “Even after developing this for years, I’m afraid that, like most men, my taste is my wife’s: sort of minimalist and white. Well, it was when I left this morning. Unless she’s gone online and bought something else. . .”

www.mydeco.com

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