Guinness, as the old saying goes, is good for you. And for your bank balance too, it seems. A collection of Guinness advertising ephemera is expected to raise more than pounds 50,000 when auctioned by Christie's next week, Wednesday September 11. Items for sale will range from a set of Carlton Ware Toucan lamps, each valued at pounds 500, to cuff-links and Toucan wallpaper.

"The appeal is really very simple" Christiie's spokeswoman Jill Potterton explains. "Individually, Guinness-ware is highly affordable. Overall, it is especially popular thanks to its design and the fact that advertising- ware in general is fast becoming a highly collectable area."

Creating hype to stimulate a cult following is one thing - witness the number of household products currently offering logo emblazoned 'collectables' - but generating appeal that stands the test of time, for financial or nostalgic reasons, is quite another. Little Nineties ephemera will still be around in a year's time, let alone 50, believes Robert Opie who runs the History of Packaging Museum in Gloucester Guinness' earliest appeal was built on illustrator John Gilroy's menagerie of Guinness-guzzling animals which appeared on posters in the Twenties and Thirties. Guinness then developed a range of memorabilia primarily for promotion in pubs - in the Forties and Fifties and it is many of these products which enjoy particular enduring appeal.

Although the company today manages a comprehensive merchandising operations with its own shop and visitor's heritage centre in Dublin, it has also moved with the times - latest spin-off products include a Guinness computer screen saver featuring the dancing man well-known from a recent cinema and TV advertising campaign.

Even so, the mass-produced approach invariably runs counter to attempts to manufacture a cult. And it lessens the potential for products to eventually become collectables, Opie says. "If too many items are produced, future desirability will be dampened by over-supply," he explains. And the questionable relevance and quality of many items lessens their long term appeal. "A book or video of the ad is little more than a promotional gimmick, and don't believe anyone who tells you anything else. It's here today, gone tomorrow."