A decade ago, the PC was the center of the digital world. Web TV aside, a full-scale Windows or Mac OS PC was the only reasonable way for ordinary people to get on the Internet. People also used their PCs to write term papers, organize their music and photos, edit video, play games, and a lot more.

But today, conventional PCs face a growing army of cheap, special-purpose rivals. No single device is an adequate PC replacement all by itself. But together, the growing menagerie of devices is making PC ownership less and less necessary for ordinary consumers.

This week's Consumer Electronics Show demonstrates just how far this trend has developed. Most of the big product announcements were related to post-PC gadgets. And product roadmaps from Intel and others suggests that the decline of the PC will only accelerate in the coming years.

Post-PC products

One sign of decline of the PC is the surprising popularity of Chromebooks. On the heels of strong holiday sales for other companies' chromebooks, Toshiba announced its first Chromebook this week.

On the surface, Chromebooks look a lot like other laptops. But as this dismissive ad from Microsoft makes clear, they're actually limited, special-purpose devices:

Microsoft is right: if you want to do serious spreadsheet wrangling, photo editing, or software development, a Chromebook probably won't cut it. But most people have no interest in doing those things outside the office. If, like millions of people, you mostly want to check Facebook, read your email, and watch YouTube videos, then a ChromeBook works just fine. And ChromeBooks aren't only cheaper, they also avoid many of the hassles and pitfalls—software updates, malware, baffling error messages—of Windows PCs. Most users don't actually need all the features of a standard PC, and for them the extra complexity just means more headaches.

Tablet computers have emerged as another major threat to the conventional PC, and it too is expanding aggressively into turf once dominated by Windows. Samsung announced a new 12-inch tablet at this year's CES. It has a split-screen multitasking feature that helps take advantage of all that screen space.

Hard-core gamers have long been a key market for PCs. Gaming consoles aren't new, of course, but the most sophisticated and powerful games have always relied on the superior horsepower of a full-scale PC.

That may be about to change. This week one of the most prominent figures in the PC gaming world, Valve, unveiled a line of special-purpose gaming devices designed to entice PC gamers into the living room. These Steam Machines are manufactured by more than a dozen different manufacturers. Prices start at $499—comparable to the recently-launched XBox One, and will almost certainly fall over time. Other Steam Machines cost thousands dollars; they should have enough computing power to satisfy even the most demanding gamers. Every Steam machine sold will be one less reason for a consumer to own a general-purpose PC.

Smaller, cheaper, and more flexible

Meanwhile, Intel is hard at work on chips that will enable the next wave of post-PC innovation. In a Monday speech, Intel CEO Brian Krzanich unveiled Edison, a new line of tiny, cheap, low-power computer chips. The chip company also showed off a new generation of wearable computing devices: "a smart watch, smart earbuds, a smart earphone headset called Jarvis and a charging 'bowl' to put all the gadgets in when they need powering back up."

Samsung is working on display technologies that could make the next generation of post-PC gadgets more versatile than ever. Not only do the new Samsung TVs unveiled at CES have curved screens, but a prototype device features a 105-inch screen that bends.

That might not sound like a big deal, but as Matt McFarland pointed out Tuesday, Samsung has big plans for flexible, durable screens. A recent video envisions turning our tables, floors and windows into touchscreen displays. Samsung also envisions a touchscreen wrapped around a coffee cup, and another curved display that doubles as a cutting board:

Right now, no one is clamoring for computers in their wristwatches or tables. But the combination of tiny, cheap computer chips and increasingly strong and flexible displays will eventually mean powerful computational capabilities being integrated into a wide variety of household objects. People made fun of the concept of $3,000 tweeting refrigerators when Samsung unveiled it at CES three years ago. But the only thing that's laughable about the idea is the price tag. If, a few years from now, Whirlpool can put an Android-powered touchscreen computer into the door of your fridge for an extra $50 (or, even better, turn the entire door into a giant touchscreen), why not do it? It could be a convenient place to keep a to-do list, check the day's weather, or display pictures of the grandkids.

The general-purpose PC became the dominant computing paradigm of the late 20th Century because computing hardware was too expensive and cumbersome for most families to own more than one or two of them. But processing power is getting smaller and cheaper, while display technologies are getting more flexible and powerful. The PC was the jack of all trades, but master of none. In contrast, special-purpose designs can be tailor-made for a specific application. As those devices become smaller, cheaper, and more versatile, the cost, size, and complexity of conventional PCs will be more of a turnoff for ordinary users.

Obviously, PCs won't go away completely. After all, IBM still has a thriving business selling mainframes. But the era when the PC was a major platform for consumer innovation is over.