Recently, I reported on fears that WiFi could give us all cancer. The possibility appeared remote – indeed figures indicated that we are 100,000 times more likely to be killed by Radio One transmissions than an AirPort connection – but there’s no doubt that the wireless euphoria was dampened somewhat. Suddenly the idea of all of us laptop users shopping at Amazon or bidding on eBay while in our local coffee shop or down the end of the garden took on a less healthy glow.

Talking of glows … just when you thought it was safe to warm your trousered thighs with an underplate of anodized aluminium, along comes an even more scary portable problem: exploding laptops.

Oh, it was amusing when we learnt that Dell’s laptops were spontaneously combusting all over the world, maiming Windows users and scorching conference tables, but those smug smiles were wiped from our faces when we realised that the same sizzling Sony batteries were used in Apple’s otherwise superior portables.

Now Apple has to follow Dell in recalling over a million possible arsonist laptops, and none of us could quite look at our shiny PowerBook or iBooks again with quite such confidence.

According to Apple, this problem does not affect its latest Intel-based MacBook or MacBook Pro models. This surprised me as these lovely laptops are getting something of a reputation as portable heaters. They might look cool, but they’re mighty hot to touch. Even Apple warns users not to place the new portables anywhere near their bodies for fear of singeing our legs… or worse…

Just days before asking PowerBook G4 and iBook G4 users to check the serial numbers of their batteries, Apple released a firmware update for its MacBooks that improved “power and thermal management” issues, particularly “fan behaviour”.

Data from IDC and Gartner Dataquest indicates that Apple sold close on a million Intel-based laptops in the second quarter of this year – a year-on-year increase of 60 per cent. At the same time, Apple’s Intel-based desktop computers saw sales volume decline 20 per cent, year on year. This decline is likely to be reversed now that Apple has the super-powerful Mac Pro available, but it’s clear that anything that harms laptop sales – such as their ability to set your family on fire – isn’t good news for Apple.

But it doesn’t appear to be as bad news for laptop users as was originally feared. Indeed, a quick tour of the comments on Macworld’s user forum sees a bunch of excited PowerBookers. Some are even depressed that their battery isn’t labelled a killer. As most of the affected laptops are up to three years old, the opportunity to be given a completely fresh, new battery for free is rather enticing. Batteries become less efficient the more they’re used and recharged, so a nice new one effectively restores your old laptop into a sprightly young portable – albeit one without dual-core processors and a glossy screen.

Every smoke cloud has an aluminium lining…