Is Apple's PDA a ghost of a machine?

Apple has been accused of forcing a fan site to take down pictures of a new handheld computer that could be the star of next week's much-hyped Macworld Expo.

Excitement about the show has grown since a message on the Apple site told Mac fans to "count on being blown away" when the Expo begins on 7 January in San Francisco.

Another message on the site promised the show's revelations will be "beyond the rumour sites. Way beyond."

However, Apple will be hard pressed to top the rumours spread by Spymac.com, which claims to have video of a new PDA-style product called iWalk in its posession.

According to the site, iWalk is based on Apple's OS X operating system, and will incorporate the Apple-developed Firewire data transfer technology. Wireless connectivity, Palm compatibility and even something called Gigawire have also been mooted as possible features.

A message on the Spymac.com site dated 3 January reads: "By legal request, we have removed all iWalk footage from our server. Sorry everyone, but we held out as long as we could."

However US wires are accusing Spymac.com of engineering a publicity stunt. According to Wired.com, Spymac already has a reputation for releasing spurious information and doctored images of non-existent Macintosh products.

Speculation has run wild about Macworld Expo, when the company traditionally unveils its new products. One widely-touted possibility is a flat-screen version of the iMac computer.

Apple watchers have been eagerly awaiting the company's first move in the PDA market since CEO Steve Jobs canned the Newton family of products in 1998.