Form factor, form factor ... who's got the right form factor? That's a big question for notebook buyers today, especially for those of us who suffer from notebook schizophrenia. We love the big, beautiful desktop-replacement-class machines, of which

Dell's

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Inspiron 7000 remains the exemplar, but we also go ga-ga over the

Sony

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Vaio 505s,

Sharp's

Actius line,

Toshiba's

3025CT -- the little ones.

To heck with choosing portability over power: We want both. Now.

But are even these thin-and-light wonders the ultimate design? Far from it. We see, from time to time, glimmers in other product categories of what a truly thin and light notebook might look like. Unfortunately, we usually find these alternatives don't have enough oomph to serve as our main notebook. But their form factors -- size, weight, ergonomics -- are pointers to a smaller, thinner, lighter future. And a heck of a tease right now.

I've been working for a while with a machine that I think absolutely should be the form-factor model for small notebooks as we go forward. It's exactly the right size, right weight, right volume for me, for a notebook I can easily carry anywhere, anytime. Yes, preferences vary, and what delights my idiosyncratic tastes might not satisfy yours. But I've been lending this little machine to friends and co-workers for a couple of months now to get their reactions, and the almost universal reaction has been: "I want one! They got it right!"

Indeed, I'll go so far as to say that almost all notebook PCs will look much like this one in about three years. That will take advances in screen-display technology, battery technology, power consumption and CPU heat management to get us there -- but all those are in the pipeline.

This ideal-form machine is

NEC's

(NIPNY)

new MobilePro 800. It measures 9 1/2 inches by 7 1/2 by 1 inch thick, and weighs 2 1/2 pounds. There is, believe me, magic in those proportions and that weight: Taking it with you becomes reflexive, not something you have to think about. In wireless-LAN offices, of which there will soon be many, toting a machine this size and weight will very quickly become a given, a no-brainer, for many managers and executives. Stick a wireless LAN card in the machine's PC Card slot, and you're in business.

NEC has done a great job with many of the super-small machine's challenges. For example, it has a very good keyboard -- with 17.5-millimeter key pitch, not as large as the one I use on my desktop PC, but with about as good touch, though noticeably more shallow key-travel.

But it's not yet ready for prime time as anyone's sole or primary notebook PC. First, it's a Windows CE machine. That's fine for most work. If all you use a notebook for is occasional word-processing, working with spreadsheets, dealing with email, managing your schedule and jumping on the Web, you could very happily use the MobilePro 800 today as your primary portable machine -- maybe even your only PC -- though the 800 is a great adjunct to a desktop PC.)

But a Windows CE computer can't run the broad range of Windows apps, and cutting yourself off from that treasure trove of software doesn't make sense in a general-purpose machine.

Microsoft

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has done a good job with the miniversions of Word, Excel, Internet Explorer and Outlook built into current Win CE machines and a fair job with the CE versions of PowerPoint and Access. But all are scaled-down subsets, and you bump into their limitations. PocketWord, the CE version of Microsoft Word, for example, is no Windows Write -- it's much better than that -- but there is a sense that you're using a program built on the principle of compromise. (Third-party Win CE apps are available and can be loaded onto the MobilePro 800's storage device, but in my experience, they generally suffer from the same "minified" limitations.)

One advantage of having these apps built into ROM is undeniable: Instant-on really works. Tap the power key, and you're in business in about two seconds. Tap the dedicated function keys that launch each of these apps, and you're working in a couple of seconds more. Similarly, exiting is an instant process. Of course, having your apps in ROM has a dark side: Generally you can't upgrade to newer versions without replacing the ROM chip.

The 9.4-inch, 800-by-600, 64,000-color screen is big enough, at the right resolution, but it's passive matrix, and we really need the brightness of active matrix in notebooks. Double-scan just doesn't cut it for extended use.

NEC uses a touch screen on the MobilePro 800, about which I had some reservations, but I've been won over. The machine -- any machine like this -- needs a touchpad (such as the one

Hewlett-Packard

(HWP)

incorporated into its vaguely similar Jornada), and the NEC doesn't have one. It still wants you to use a stylus for tapping on the screen to select actions. Tapping with a stylus is perfect for a Palm Pilot-sized machine, but dumb, dumb, dumb on a machine this size. A hidden (and undocumented) advantage of NEC's implementation of a touch screen: For many, maybe most, tap-for-cursor-control functions, you can just use your fingertip, which is far faster than pulling out the stylus.

The MobilePro 800 uses Compact Flash cards for storage. In an era of eight-gigabyte hard disks in notebooks, the relatively puny current 80-megabyte Compact Flash maximum capacity sounds feeble. But remember that you don't have to devote any of that storage to your basic apps. So how much memory do you really need? I've been using a 48MB Compact Flash card in my 800, and I've not yet filled half that space. Sure, using Compact Flash cards for primary storage demands a little discipline, but not much. And the ruggedness, speed and reliability of Compact Flash vs. today's notebook-sized hard disks are welcome benefits.

I can do a great deal of serious work with the 800. I don't know about you, but taken together, checking email, managing my schedule, looking up contacts' names and phone numbers, jumping on the Web and word-processing constitute maybe 85% of my time on PCs. And the MobilePro does all those very well.

So, is this MobilePro 800 my only notebook PC? No.

And I don't think it will be for a while. I carry it as my only computer on many trips and I love the machine, but I'm not yet ready to give up big notebooks. Too many things I do on the road, such as elaborate PowerPoint shows with audio tracks, still demand more power, more storage.

But we're talking about form factors here, and using this MobilePro 800 has taught me a lot about what I really want from a notebook PC and about where we're headed.

The MobilePro is a great choice for a lot of PC users today. At about $1,000, it's a steal. Even if you're not buying right now or are convinced it isn't powerful enough for you, it's worth a look just for the glimpse it provides into the near future.

Jim Seymour is president of Seymour Group, an information-strategies consulting firm working with corporate clients in the U.S., Europe and Asia, and a longtime columnist for PC Magazine. Under no circumstances does the information in this column represent a recommendation to buy or sell stocks. At the time of publication, neither Seymour nor Seymour Group held positions in the companies discussed in this column, though positions can change at any time. While Seymour cannot provide investment advice or recommendations, he invites your feedback at

commentarymail@thestreet.com.