"One small step for Inflate, one giant leap for mankind - blow hard and enjoy," says 24-year-old design maverick Nick Crosbie when I asked him for his company motto. Along with brothers Mike and Mark Sodeau, he forms Inflate, a design team which intends to test people's perceptions of modern product design. Their speciality is inflatables: egg cups, wine racks, picture frames, lampshades, fruit bowls, sofas, coffee tables. Even toasters.

"We wanted to make everyday objects which were fun to use," says Mike, 25. "Things that were fun and funky which you just don't see around. When I first bought the picture frames and fruit bowls in to show someone at American Retro, a customer paying at the till wanted to buy them immediately. Her face just lit up her minute she saw them."

The idea for their inflatables germinated two years ago while Nick and Mike were at St Martin's College in London. "I made a waterproof inflatable television set for my end-of-year project," says Nick. "Everyone thought I was an idiot." Prior to the television there had been other ideas.

At the same time, Mike dreamt up an inflatable postcard. Much like a big plastic wheat puff, this smacks of the ultimate in anarchic design. "But it does work," counters Mike. "The best ballpoint for it is a Bic and it will go through the postal system franked and all and arrive still inflated. I've received several myself." The two kept quiet about these ideas until they left college and then decided to form Inflate.

While they admit that making prototypes of plastic inflatables is a lot cheaper than if they were using other materials, coming up with the designs themselves has been a slow, hit-and-miss process. "We've had to go out on a limb and take risks with every product," says Nick.

"The problem is you have to design and work flat," says Mike. "So you can only see what things look like once they've been blown up." This causes particular problems for the bigger objects because, once inflated, a lot of things just end up round-shaped.

When probed about their drawing-board failures, it is hard not to laugh. "We tried to make an inflatable colander once," says Mike. "And an inflatable cafetiere." While these sound just plain daft, they take impossible design ideas seriously. "The more ludicrous, the bigger the challenge," says Nick. "The challenge is having to redefine the whole design concept of just, say, a lamp or a fruit bowl. It forces us to think of new ways to make something very simple in 3D."

While some things take days of trial and error, other inflatable ideas are born spontaneously. "I had an awful day once, nothing had gone right," says Nick. "So to get myself out of the bad mood, I went off and designed something I really liked - a wine rack. Now it's part of our product line."

The prices of Inflate's products are surprisingly reasonable. A packet of four inflatable egg cups costs about pounds 10, the fruit bowls about pounds 16 and the coffee table pounds 100. Only the sofa, available on a made-to-order basis, is rather more steeply priced at pounds 600. With furniture, they are willing to take one-off commissions. I ask how long it would take to whip me up a lime-green inflatable chaise-longue. "Oh, about a week," says Nick.

While their products and furniture are certainly eye-catching and off- the-wall, what about the obvious drawbacks to air-filled sofas and the like - in short, punctures? "The PVC we use to make the products is extremely tough," assures Nick. "You'd have to take a knife and rip it up to puncture it." Nevertheless, inflatable furniture is not exactly designed for a married couple who smoke and have children and a dog.

However, they are determined to keep up the work. "For years people have told me what we do is silly and it will never sell or work," says Nick. "Which is why we have the greatest pleasure now in seeing Inflate do well and our products selling in the shops."

Another young designer is also grappling with the art of inflatables. "I fell in love with the inflatables that were made in the Sixties," says Emma Salmon, 25, who specialised in plastics at art college. "I loved the great big blue transparent armchairs that Alessi made, they were very sci-fi, very 2001." Today, she feels there is scope for resurrecting inflatables, due to the existence of more sophisticated plastics. "Printing facilities for PVC are so much more advanced these days," she says. "You can now get metallic PVC, or PVC which is embossed with raised patterns; it's very beautiful."

So far, her collection includes a large zebra-print inflatable armchair (retailing at about pounds 130) and cushions (pounds 20), also available on commission- only basis. She agrees that inflatable furniture has its drawbacks, and warns about keeping cigarettes away from them, but then adds that inflatables have their advantages, too: "They're easy to pack away: you just deflate them and fold them up, and they're easy to clean - just use a sponge."

Is this something that is going to catch on? "Definitely," she says. "In fact, I'm going back to college to do an MA and specialise in inflatables."

And what does the future hold for Inflate? "Ashtrays," says Nick. "I'm already working on one and I'm pretty sure I figured a way to make them work." I laugh, but he is serious. Maybe there will be an inflatable object smokers can use after all.

If you fancy inflatable furniture but cannot afford it, use old lorry and tractor inner tubes as bean bags. They cost from pounds 15 at National Tyres and Autocare. Call 0800 626666 for branches.

Inflate products are on sale at: American Retro, 35 Old Compton Street, London WI (0171-734 3477), and Space, All Saint's Road, London W11 (0171- 727 0134). Enquiries: 0171-251 5453. Emma Salmon Designs: 0171-285 1079.