It doesn’t take a genius to notice that computers keep getting smaller over time. I mean:

Intel Compute Stick: The Windows PC That's Smaller Than a Snickers Bar

There’s no telling where the shrinking will end. But I will tell you this: We’ve reached a new milestone. This is the world’s smallest Windows PC:

It’s called the Intel Compute Stick, and it’s really small (4 x 1.5 x 0.5 inches) — so small, you might mistake it for a USB flash drive. It’s the first Windows PC you might lose in your bag. If you were a movie character being chased by techno-terrorists, you could slip the whole thing into your sock.

Better yet: It’s not only the smallest Windows PC type in the world; it’s also the least expensive: just $150 (with 2GB of memory, 32GB of storage, and Windows 8.1).

What you get (and what you don’t)

You might be wondering, is this really a PC? Normally, the ingredients you expect include a processor, memory, storage, a screen, expansion ports, speakers, a mouse or trackpad, and some kind of keyboard.

Clearly, the Compute Stick doesn’t have a built-in keyboard; if it did, you’d need fingers the size of hydrogen atoms. And it doesn’t come with a screen. Instead — and this is the really cool, liberating part — you plug the thing into the HDMI jack of any TV or monitor, like this:

That’s right. Instead of plugging a monitor into your PC, you now plug your PC into the monitor. And by the way, it’s very cool to plug it into a big TV, like the one in your living room. You could do Windows demos that they could see in Russia.

Intel includes, in the box, a tiny HDMI extension cord that accommodates TVs whose back panels don’t fit a rigid plug like the Compute Stick.

You also have to plug the Compute Stick into a power supply, which is a small downer; it’s just not as self-contained as you thought it would be.

And you need to supply your own keyboard and mouse. A Bluetooth wireless set works especially well, because the Compute Stick has only one USB jack; it’d be a shame to plug it up with a keyboard. (Beware, however: You must use a wired USB keyboard and mouse to set up your Bluetooth keyboard and mouse.)

There’s also a cool Android app called Intel Remote Keyboard that turns your smartphone into a mouse and keyboard. That makes for an insanely portable setup.

But the Compute Stick does contain most of the stuff you’d expect to find inside a standard-sized PC: processor, memory, storage, power supply, Bluetooth, WiFi, graphics circuitry, a microSD memory-card slot for expansion, even an itty-bitty fan to keep it cool. (You know that only by the presence of vents — the fan itself is silent.)

What it can (and can’t) do

Now, to calibrate your expectations: This thing:

is not this thing:

Online, people (and some surprisingly harsh reviewers) have complained that the Compute Stick can’t run professional video-editing apps or VMWare or 3D games. But that’s like complaining that your $4 flip-flops slowed you down when you ran the marathon. If you’re trying to run Halo on a $150 computer the size of a USB drive, you’ve got the wrong tool, bub.

Instead, think of the Compute Stick as an inexpensive, super-portable computer with enough horsepower for normal, everyday computing things: email, instant messaging, Web browsing, word processing, spreadsheets, Microsoft Office, Quicken, and so on. It’s also great for streaming music and video: In my testing, YouTube, Netflix, and Hulu all played smoothly and flawlessly.

But no, a PC this small, with this modest a processor (an Atom Z3735F, if you must know), doesn’t have the juice for more ambitious applications.

The Compute Stick has other limitations as well. Chief among them: There’s only one USB jack. (And it’s USB 2, not the more modern USB 3.) If you want to plug in a hard drive, USB keyboard, and flash drive simultaneously, you’ll have to add a USB splitter box.

Most USB hard drives — even some that draw their power from it — work fine with this jack, but not all. Some drives draw more power than this jack can deliver. Bottom line: If you want to expand the Compute Stick’s 32 GB of built-in storage, your best bet is to add a MicroSD memory card (up to 128 GB).

Other limitations: If you’re using WiFi heavily (streaming a movie from Netflix, say), the Compute Stick’s Bluetooth connection can get skippy; your cursor may jitter when you move your Bluetooth mouse. More than one online commenter has complained that the Compute Stick doesn’t work with Vizio TV sets. And there’s no headphone jack. (Were you really going to listen to music crouched behind your TV, where this thing is plugged in?)

Look on the bright side

But come on: This is a Windows PC that’s half an inch wide. It’s far more portable than a laptop, a tablet, or even a compact hard drive.

It turns any TV into a PC, making the Compute Stick a great potential space-saver for dorms, restaurants, or Tokyo apartments. You can grab your entire PC and bring it with you to a conference room. It’s so cheap, it’s almost an impulse buy — maybe as a second PC or a kid’s machine. Intel also notes that it’s well-suited to turning screens into digital signs, slideshows, or kiosks.

The Compute Stick isn’t the first computer on a stick. There’s the Asus Chromebit, which is similar but runs Google’s Chrome OS. There’s the Raspberry Pi, which most people run Linux on. There are also, of course, streaming-TV gizmos like the Amazon Fire Stick.

But none of those products run Windows or the 4 million programs that run on it. The Compute Stick comes with Windows 8.1 preinstalled, but you’ll be able to upgrade it to Windows 10 when that OS ships later this month. (It’s also available in a $110 version that runs Linux.)

Intel says that other companies will be introducing their own spinoff versions of the Compute Stick. Lenovo, for example, will soon release its Ideacentre 300 —a virtual clone of the Intel Compute Stick, but costing only $130.

Intel hints that more powerful, faster Compute Stick models are coming later this year. An upgrade to newer, faster WiFi (802.11ac) is coming, too.

In other words, minuscule computers are a thing, and they’re only going to become more so.

Will anyone ever replace this:

with this?

Of course not. But as they say: The marvel is not that the bear dances well, but that the bear dances at all. And for a computer small enough to tuck behind your ear, Intel’s Compute Stick dances surprisingly well.

David Pogue is the founder of Yahoo Tech. On the Web, he’s davidpogue.com. On Twitter, he’s @pogue. On email, he’s poguester@yahoo.com. He welcomes non-toxic comments in the Comments below.

Intel Compute Stick: The Windows PC That's Smaller Than a Snickers Bar

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