The original Asus Eee PC took the hardware world by storm. Small, lightweight, inexpensive, yet running a full-fledged OS, this tiny device offered laptop capabilities at near-PDA pricing. Asus has since expanded its Eee PC line with models of varying capabilities, and competing devices are now arriving from other manufacturers, including Acer, Dell, HP, and MSI, among others. Collectively, these devices have come to be called "netbooks."

So far, netbooks have been marketed primarily to students, hobbyists, and cost-conscious consumers, but their unique characteristics make them attractive to many professionals, as well. I decided to find out how well they would stand up to an average business workload.

As I mentioned, the netbook category is rapidly expanding. The two devices I looked at -- the Asus Eee PC 901 and the HP 2133 Mini-Note -- don't represent the entire market. Other current or forthcoming devices may suit your specific needs better. But between these two machines I was able to get a rough impression of the options available from most manufacturers, their relative advantages, and the trade-offs involved.

Pack a bag

Asus and HP both offer Linux pre-installed, but with business travelers in mind, I tested the Windows versions instead. A proper test naturally meant air travel; so I stuffed both machines into a standard carry-on bag with room to spare and booked my ticket.

Don't be surprised if you're interrupted by curious onlookers during your flight. These micro-sized PCs definitely get noticed -- something that business travelers may want to consider. The HP 2133 looks steely, sleek, and space-age; the Eee PC, like an overgrown makeup compact. If first impressions matter, the HP projects a more professional image.

HP markets the 2133 to business users, but like the Eee PC, it's really best suited to Web browsing, e-mail, and light office tasks. Don't expect an entertainment center, either; netbooks have no optical drives, so you won't be watching DVDs on long flights, and both models I tested even struggled to play MPEG-4 video from the internal drives.

Overall, these machines are purpose-built with a limited range of applications in mind. If it's a full-featured notebook you want, stop reading: Netbooks aren't for you. If, on the other hand, you can see the utility in a compact, lightweight, inexpensive secondary PC, a netbook could be the ideal travel companion.

They're no powerhouses

Just how timid are these netbooks? The Eee PC 901 was the first device to ship with Intel's new, mobility-minded Atom processor, and at 1.66GHz I could definitely tell the difference between it and a desktop Pentium. Launching programs and switching tasks, in particular, seemed sluggish -- though it was hard to tell how much of that was attributable to drive performance (more on that later).

The HP 2133 model I tested used a Via C7-M mobile processor running at 1.2GHz. Performance was acceptable but not impressive, which could partly be the fault of the OS. The 2133 shipped with Vista Home Basic, which seemed like extreme overkill. Vista Business is also available, but XP -- which ships with the Eee PC and seems much more appropriate -- is not an option.

The 2133's Windows Experience Index was a measly 1.7 (owing to the CPU), and Vista's tendency to maintain lots of background processes runs contrary to the netbook concept. HP is reportedly switching to the Atom CPU for future Mini-Note models, but unless it loses Vista I wouldn't expect much of a speed bump, based on the Eee PC 901's performance.

What you lose in performance with these devices, however, you gain in battery life. Despite weighing just 2.63 pounds, the HP 2133 gets a decent 2.5 hours of run time. Asus, on the other hand, claims a whopping 7.8 hours of battery for the 2.43-pound Eee PC 901, thanks to the extremely low power requirements of the Atom chip. That claim is exaggerated, but in real-world use I managed a very respectable 5.5 hours with Wi-Fi enabled.