Generally speaking, the most important criteria when choosing a notebook are size and weight. But if you are looking for a desktop replacement or even a slightly smaller mainstream system, those considerations take a backseat to performance and features. These systems may look portable, but the fact is that they are really suitable only for occasional business travel. Desktop replacements can exceed 10 pounds when you throw in the AC adapter, and even the smallest mainstream systems weigh more than 6 pounds.

That may not sound much heavier than some thin-and-lights, but even a few ounces can make a big difference if you spend any time on the road. However, if you need a system primarily for your home office or small business that you can move easily from time to time, a mainstream or desktop-replacement notebook is an excellent choice.

A desktop at heart
The biggest development in this category has been the adoption of desktop components, specifically processors and supporting chipsets. By using a desktop Pentium 4, for example, manufacturers can configure notebooks with processor clock speeds in excess of 3GHz, and they can do it at more aggressive prices since desktop parts are cheaper. The result is better bang for the buck, though there's a trade-off in terms of battery life. To address this market, Intel released a Pentium 4-M, a hybrid similar to the Pentium 4 but with Intel's battery-saving SpeedStep technology for notebooks.

Don't confuse this with the Pentium M, part of the Intel Centrino technology initially found only in smaller notebooks. Though the Pentium M has much slower clock speeds, it still delivers excellent performance and increasingly is finding its way into desktop-replacement systems as well.

Get the big picture

Big and beautiful HP Compaq Presario X1000 IBM ThinkPad A Toshiba Satellite P25 series Apple 17-inch PowerBook G4 Notebooks for tight budgets Dell Inspiron 1100 Apple iBook Acer TravelMate 290 IBM ThinkPad R40

In addition to size and weight, the type of notebook you choose will also dictate the screen size and other features. Apple set the bar with its 17-inch PowerBook G4, and now several manufacturers offer 17-inch models, but 15- and 16-inch displays are the norm. Wide-screen displays are also coming on strong. Instead of the 4:3 aspect ratio of most computer displays and TVs, these systems have the 16:9 aspect ratio found on wide-screen TVs. This makes them great for watching DVD movies in their intended format, and their WXGA resolution (1,280x768 pixels) also gives you more screen real estate, either for viewing two documents side by side or for working in multiple programs at once.

The combination CD-RW/DVD drive has lessened the need for two drive bays, but all desktop-replacement systems still offer both. Because they are swappable, this gives you the flexibility to drop in a second hard drive or an extra battery in place of one of the drives. At one time, mainstream or value notebooks were distinguished by their two fixed drives, one of which was typically a floppy. Many now have swappable drives, and in order to save weight and cost, some include only one optical drive, making them more akin to budget thin-and-lights.

What to choose
No single configuration will be right for every business user, but for most, we recommend a desktop-replacement system with a Pentium 4-M processor, 512MB of memory, an 80GB hard drive, a 15-inch display, a CD-RW/DVD drive and DVD burner, and integrated wired and wireless networking. If you are on a tight budget, a mainstream system with a desktop Pentium 4 processor, 256MB of memory, a 40GB hard drive, a 14.1-inch display, a CD-RW/DVD drive, and integrated wireless and wired networking, should give you plenty of PC for about $1,000.

As with desktops, when you are buying a bunch, your best bet is to stick with a single vendor and product line. Some corporate notebooks, such as the HP Compaq Evo, the Dell Latitude, and the IBM ThinkPad, use the same components across most or all of the line, which means that you can use the same drives, docking stations and port replicators, and AC adapters with any system--a big advantage in business. Finally, we recommend that you invest in spare or extended batteries for employees who make cross-country flights.