After all, if Sainsbury's and Debenhams can sell own-brand magazines, why shouldn't Cosmo sell handbags and healthy snacks? And if Versace and Ralph Lauren and Calvin Klein, not content with the couture and ready- to-wear markets, are hell-bent on flogging an entire "lifestyle" - wake up in Ralph's sheets, eat off Gianni's plates and slip into Calvin's knickers - why shouldn't Cosmo open a cafe?
Its National Magazine Company stable-mate, Good Housekeeping, ran several restaurants in the 1920s and Thirties, and presently makes a tidy sum selling cookery books and kitchenware, just as House Beautiful does with wallpaper.
Look what Disney did with a mouse, seems to be the motto of Terry Mansfield, managing director of National Magazines and eager proponent of "masthead marketing". "I went to Niketown the other day and I walked around this incredible store in Madison Avenue," he says. "I went from there to Coca- Cola, to the Hard Rock cafe, to Planet Hollywood. I went to Harley-Davidson. I thought, if somebody who produces motor-bikes can sell aftershaves and fragrances, then I can develop magazine brands."
And last Friday, he was surveying his new, albeit temporary, domain: the Cosmopolitan Show at the Earl's Court Exhibition Centre. Thousands of young women, paying pounds 8 or pounds 10 each for tickets, wandered around the hall where eager exhibitors lay in wait for the retailers' holy grail: the Target Audience.
Clarins, Boots No 7, Estee Lauder offered make-overs and beauty tips; Nicky Clarke, Vidal Sassoon, Andrew Collinge (and their minions) explained the finer points of hair maintenance. Salon Selectives even had a trampoline (complete with safety harness) for punters inspired by the exhortations of those performing on the health and fitness stage.
And on the catwalk, models who were uniformly tall, thin and pretty yet somehow ordinary, emblems of an attainable dream, showed Christian Lacroix but also Wallis and Kookai and Morgan, the kind of clothing that any Cosmo reader could afford.
You could see why Persona had bought a stand - its staff at the ready to field questions about the 400 women who have become pregnant while using the new contraceptive - but what about Mailbox Marketing, whose stand consisted of some brochures and a stack of cardboard boxes?
Because, it emerged, the boxes contained free samples of Colgate Sensation, a new toothpaste, which is "young, trendy and female-orientated", according to Patrick Noone of Mailbox. And what makes Sensation groovy and feminine? Why, the fact that it is a freebie at the Cosmo show!
Masthead marketing and brand extension is clearly a two-way street: retailers at the Cosmo show were hoping for approval by association and contact with the very people they most want to woo, while the magazine makes lots of money and provides its readers with a service that should ensure their loyalty.
Get it right, and the business benefits are huge. Young women can be seen all over London carrying bags with the logo of Elle magazine, and each one is giving the magazine free publicity. Get it wrong, and you will damage the brand.
Elle, owned by Emap, has also launched a line of clothing - sporty, casual clothing that does not compete directly with the expensive and fashionable ranges advertised in its glossy pages. According to Marketing Week, the Daily Telegraph was told that advertisers would pull out if it launched its own financial service products. For that reason, Cosmo would not launch a range of cosmetics, for example. And it is one thing to start with a tangible product - a drink, a motorbike, a shoe - and use the name to sell more products, but quite another to cash in on a feeling, a philosophy almost.
"Cosmo is a real life-force - it's given birth to a whole generation of women. It's not just a fashion catalogue," says Mandi Norwood, the editor. "So we've got a much more challenging job because our readers trust us so much that if we get it a bit wrong it could be a major disaster."
None the less, Ms Norwood says that women's magazines are under assault from all sides: newspapers publish health and beauty columns, TV shows offer emotional advice and department stores give fashion tips. Therefore, "We have to keep one step ahead."
Hence Mr Mansfield's expansion plans - which include television versions of his magazines. Until recently, "masthead programming" was banned by the Independent Television Commission, partly because of restrictions on cross-media ownership and partly for fear of encouraging advertorial programming. The ITC has now relaxed the rules, allowing such shows to be broadcast on cable and satellite stations, if not on terrestrial channels. National Geographic already has a television channel that screens documentaries which are more or less moving versions of the glossy photos and lengthy articles on endangered species (animal, vegetable and human) for which the magazine is so famous. Good Housekeeping and Granada have teamed up to make a programme for BSkyB, and Cosmo TV could be next.
In any such deal, the original brand will almost certainly join up with a manufacturer in the chosen field - National Magazines is not going to set up as a maker of clothing, for example, because it is a competitive and specialised marketplace. Cosmo would be more likely to set up licensing deals - but that brings its own risks.
Last week, the Spice Girls were reported to have sacked the company distributing their Girl Power merchandise following complaints from hundreds of fans. There is no point in extending the brand if the extensions are going to dilute the brand's strength or alienate customers at the heart of the operation.
So any product chosen to bear the Cosmo name must first represent financial value, and then embody the brand's value. The magazine's readers may enjoy DIY and Mrs Doyle from Father Ted, but a Cosmo offer of house paints or house-coats would surely fall flat.
As Vivien Measor, a financial advisor visiting the Cosmo show with a friend, pointed out, you wouldn't buy a Cosmo product "unless you wanted it anyway". But then again, we punters are sometimes oblivious to the dark arts of salesmanship.
Sonia Ford, make-up consultant at Boots in Milton Keynes, and a supervisor, Debbie Ethridge, were prowling around the Cosmo show checking out the competition. They would be happy to stock products bearing a Cosmo label: "I think if it had the Cosmo name on, it would sell better," Sonia says. "It's a very fashionable magazine," Debbie adds.
And we are nothing if not persuadable. Teresa Hazell, camcorder slung around her neck, was lurking near the catwalk. Would she buy a Cosmo product? "I don't even read Cosmopolitan. I'm just here to see Louise." Well what if Louise, the former singer with Eternal, was to endorse a product line. Would she buy that? "Oh yes"n