Apple Inc. announced an addition to their portable computer line during this month’s MacWorld Expo: the MacBook Air. As I watched this entry into the “ultralight” laptop space, my thoughts turned to some of my issues with mobile computing, and why I’m not looking forward to providing Air support.

For most people, the question of what kind of computer to get is usually pretty simple. In spite of what you might think given the inspiration for this post, that question is not “Mac or PC?” The question is “Desktop or Portable?”

Having to choose between these two options is still a reality for most people (and even most smaller companies) because the budget doesn’t allow for providing two computers to a single individual. If you need to travel with a computer, then you’re probably getting a portable. At least now it’s possible to afford a portable “desktop replacement.” The first portable computers were completely unsuited to being one’s primary machine, since they were underpowered and offered limited connectivity options.

Now, however, it seems simple portability isn’t enough for us. Manufacturers have split the market for mobile computers into a number of specialized sectors. The Ultra Mobile PC, tablet PCs, palm-tops, even wireless handsets are all competing to be the must-have device that we carry on the road. The MacBook Air is an example of another type, the ultralight laptop. Apple isn’t the only company to sell such a device. Formerly IBM, now Lenovo, Dell, Sony, Toshiba, all of these companies have a product available that is aimed at a very particular market segment.

What segment is that?

As I see it, the ultralight laptop is intended to be the second computer for the price-insensitive business traveler. Woe to the help desk that has to support such users, because ultralights are the epitome of a bad trade for style over substance, and they make the business of supporting business computing much more difficult.

The manufacturers of ultralights have to make a number of compromises in order to get the size and weight of their products down to the point where they’ll get executives drooling. Optical drives are left off; expansion ports are sacrificed. Keyboards are smaller that most adults can use comfortably, and screens are shrunk to the squinting point. This type of machine has so many sacrifices made in its design that it cannot be anyone’s sole computer. (At least, not without, adding several accessories.)

When compared to more capable business laptops, ultralights don’t make sense to me. For a couple of pounds more, and a thousand fewer dollars, one can have a computer that meets their needs at home and away. Since the difference in relative weight they offer doesn’t seem that significant, ultralights just wind up seeming indulgent. They come off—to me—as a way for executives to show off to colleagues and bystanders: “I’m important and/or wealthy enough that I have a computer that I use only while traveling.”

When it comes to ultralight portable computers, I think the technology industry has again accomplished what it does best: It’s found a way to sell us a product we don’t really need.