Comfy eye-catching footwear beloved by Hollywood celebrities and the English middle classes, or a fashion disaster in which the right-minded would not be seen dead - Crocs have divided opinion for much of the past decade.

The harsh realities of the business world seem to have caught up with the Nasdaq-listed maker of the foam clogs after its shares almost halved overnight on a forecast of slumping sales.

Crocs Inc last night warned of its first drop in sales since it was founded at the turn of the millennium as retailers started cutting back orders. This follows a 20-month, sevenfold surge in sales after the company floated on the stock market in 2006.

Crocs shares now stand at less than a tenth of their peak value. The firm claims it is a victim of cash-strapped Americans. Critics, which include the internet blogger I Hate Crocs Dot Com say the fad is finished.

Hollywood A-listers Jack Nicholson and Desperate Housewife Terri Hatcher have been snapped in their Crocs, but the clogs have also been a constant source of controversy.

News of children's Crocs getting caught in escalators was followed by a row in British hospitals, where they have become the chosen footwear of many workers. Health and safety executives said Crocs could be unhygenic and spread disease.