You can never be too rich or too thin, especially when it comes to Hewlett-Packard's new Sojourn notebook. This sleek new portable will be the talk of first class-- but you'll have to pay first-class rates to get it.

It has the dimensions of an IBM 560, with a 12.1 inch screen, but at less than 3/4 of an inch, the Sojourn is ultra-ultra thin. It's still got lots of power inside, with a 233Mhz Pentium processor, 64 megabytes of RAM, and a 2.1-gigabyte hard drive.

The Sojourn also does the best job of adding on slices that I've seen yet. Two slices come with the package, one that adds in a CD-ROM, floppy, standard ports and speakers, and the other provides a two- or three-hour lithium-ion battery.

You'll need that battery, because the 3-pound main unit delivers a little over an hour on the built-in battery. And because that battery is not removable, you'll find yourself carrying that pound-plus unit whenever you leave town. The two units together weigh about the same as IBM's 560, but you do get longer battery life.

It sounds like a great package, but there are two main drawbacks. First, because the system is so thin, the keyboard is awful. Rather than mechanical keys with standard travel, the Sojourn uses a membrane-style keyboard that reminds me of the PC Junior. When I tried to touch-type on it, my fingers skittered all over the keys. Don't expect to type more than a few words per minute. Second, at almost $7,000, this machine is not for wusses. You really have to spend heavy to get something this svelte. If the company pays for first class, and your computing needs are light, this might be the machine for you. If you've got cash to burn, and you've already bought that 20-inch NEC LCD monitor, rush out and buy a Sojourn.

If you're looking for a real workhorse, though, there are a two other new notebooks you should consider-- Micron's Go Book and Dell's Inspiron 3200.

The Go Book is built around a Pentium, not a Pentium II, but that was the only drawback of the prototype I looked at. The GoBook, in fact, looks a lot like IBM's 560, but they managed to fit a multifunction bay into the 1.3-inch-thick unit. That bay can fit either a CD-ROM, floppy, or the standard battery. It's an efficient design, because you can't operate the CD-ROM or floppy on battery power anyway.

Still, the design is fairly standard, except for the GoBook's innovative slice. Much like the Sojourn, you can attach a lithium-ion battery to the bottom of the unit and extend the system's battery life to 11 hours, according to Micron. But as we all know, "vendor hours" are usually double what you'll get in real-life, so expect 5 or 6 hours of continuous use. That's still better than any other system I've seen. The GoBook with the external battery bay starts at $2,600, and is perfect for the mobile professional on a budget.

And for the real heat-seekers on a budget, Dell's new Inspiron 3200 is a great compromise. It includes Intel's new Pentium II processor, a 13.1-inch screen, and you can run the floppy or CD-ROM from the internal battery. A 266Mhz system starts at under $2,900, and you can get a 233 for $100 more than the GoBook. If you want the fastest power, a super-large screen, and a great price, the Inspiron is for you.