Laptops allow staff to work anywhere. However, they also allow staff to do other things - break the keyboard or screen, drop the thing under a bus, or render it unusable because their family has misused it while it was at home.

In other words, staff working happily on desktop PCs can become a liability when they are packed off with mobile machines. Any small business moving to mobile working is going to have to - at the very least - balance these extra costs against the benefits they expect to gain.

"Whatever the size of a company, it needs to be 100 percent sure that the end user on the road will keep productive even if something goes wrong," says Mike Walker, mobile business development manager for the UK at Lenovo. His company has some special angles, but the industry mostly agrees on the basics.

First, the business needs to consider the reliability of the machines themselves. Over recent years, laptops have become more reliable, but they still lag behind desktops for the obvious reason that they are designed for portability, and they get moved around a lot.

According to a study by analyst firm Gartner, one fifth of laptops will fail during their lifetime. Fifteen percent will fail in the first year, and 22 percent will fail over the first four years. By comparison, only five percent of desktops will fail in the first year, and twelve percent will fail in four years, according to Gartner’s figures for 2006.

This is a big step in the right direction - in 2004, twenty to 28 percent of new laptops would fail. Much of that improvement is down to better designs - and any laptop buyer should get some detail on the screen, keyboard and hard disk of a potential purchase.

Screens used to be the weak spot of a laptop, but their odds of survival have been improved, partly by making laptop lids more rigid and providing more space between the screen and the keyboard when the lid is closed, according to Leslie Fiering, research vice president at Gartner.

Hard drives - mechanical parts vulnerable to impacts - have also been a major source of failure, but again this danger has been reduced by technological fixes, such as shock-resistant mountings. Hard drives for laptops should also have motion sensors that park the drive heads as soon as the laptop begins to fall, to prevent damage to the disk platters on impact.

Beyond this, it's pretty obvious that, as memory prices reduce, laptop hard drives will eventually be replaced by solid state drives built on Flash memory. Flash disks are more reliable, and also lighter. At the moment, though, this is an expensive option, and leads to reduced storage at greater cost.

Motherboards have become the most-often replaced component, not because of decreasing reliability, but because more components have been integrated onto the board, and any failure is likely to mean replacing the whole thing.

Keyboard failures are common, due to spillages or mechanical failure, but laptop designs now tend to be modular, to allow easy replacement. Latches and hinges also tend to go wrong eventually.

It is worth checking that your supplier, whether the original manufacturer or a reseller, keeps a full complement of spare parts. "We stock all the spare parts, and we have the lowest return rates in the industry," says Lenovo’s Walker.

Rugged machines

For anyone looking for something more reliable than business-grade laptops, there are rugged or semi-rugged machines - but for most small businesses, these will be overkill.

The best-known brand here is Panasonic's Toughbook - often seen in the hands of an AA or British Gas engineer. The other big brand is Itronix, which claims that its GoBook can be safely immersed in petrol, and then used without danger of an electrical spark causing an explosion. The firm says users can drop these machines out of a window, or drive a car over them, and carry on working.

However, most people don't actually need to do these things regularly, and most people quickly decide it isn't worth spending £2,500 or more for a laptop that will usually have a lower, slower specification than the norm, and weigh something like twice as much (4kg as compared with 2kg if you go for a lightweight model). Most users should put the money aside for the much-less-than-20-percent chance that their laptop will break irreparably in the first year.

Besides choosing the right hardware, it's possible to boost reliability by software-based techniques. "There are ThinkVantage tools on every single unit we ship out of the door, at no extra cost," says Walker. "This includes a rescue and recovery feature, based on a hard disk image stored on the laptop, and kept up to date." If the laptop fails, the last stable version of the system can be restored from the hard disk.

They also help with support: "It's always been harder to support a mobile workforce from a helpdesk," says Walker. "If end users are running into problems, it helps to log into their system remotely." Centralised management can keep software up to date, and spot when a disk is going to be full, or even when it is experiencing error rates that mean it should be replaced.

These functions have been out of the reach of smaller companies, but Intel's AMT - included in Centrino Pro - and other remote control technologies mean they can be offered through outsourcers, either as a low-cost add-on to laptop purchase, or as an ongoing management contract. "There used to be a distinct fence between small businesses and larger ones, but that is disappearing now," says Walker. "The technology is reaching all levels, and it's affordable technology now."

London-based Qual-IT, for instance, ships laptops to small businesses and individuals, and offers a remote fix service based on the widely-used VNC remote control system developed by AT&T, and a courier pick-up-and-replace service. "There's no hidden costs, and we usually come in cheaper than buying the laptop direct from the manufacturer," says Suzanne Tompkins, sales manager at Qual-IT.

Other providers have moved up the food chain. Level Platforms started as a managed service provider, and now provides management technology based on AMT to enable other managed service providers.

"MSPs like these can handle the management of machines and do the worrying," says David Hollway, technical marketing engineer at Intel. A nominated IT person in the end user company can log into a web page and use a browser to check the health of the company's laptops on a dashboard, he says. "It might say 'here are ten machines, one with a hard disk that is 95 percent full, and another three patch revisions out of date,'" he says.

So, if reliability is a major concern over laptops, you can probably dismiss it. Laptops are more reliable, and they're more easy to manage than they used to be. And there are people out there who want to help you do it.