Cody Littley's new hard drive can only hold a single kilobyte of data—about one millionth of what you can cram onto those finger-nail-sized microSD cards—and it can't exactly slide into the back of your smartphone. But it's still an impressive creation. Littley built it himself, inside the virtual world of Minecraft.

It's one of those projects that so sharply displays the wonderfully unique attitude that drives the world's computer hackers—a class of people that has come to play such an important role in our society. Littley built his hard drive just because he could. "When I built the the device, I didn't have anything in mind that I wanted to store on it, I built it for the sake of the challenge," he says. "A surprisingly large number of commentators on Reddit think I should store 1KB of porn on it."

But the project also shows that virtual worlds like Minecraft—another staple of the modern computer universe—are far more than just games. They're a means of self-expression—and they're educational tools. Enterprising educators are already using Minecraft to teach programming, and Littley's endeavor provides a crash course the basic concepts that underpin our computer hardware.

Littley says he built his hard drive without using any Minecraft add-ons—known as mods—or Minecraft editors that let players automate the creation of larger projects. He only used the standard tools available in the game, cobbling together his hard drive block by block. The project depends largely on what's known in the game as "redstones," a type of block that transmits another in-game substance called "red stone dust."

Enterprising educators are already using Minecraft to teach programming, and Littley's endeavor provides a crash course the basic concepts that underpin our computer hardware.By using flows of this dust, players are able to build circuits and other complex machinery. Littley realized that because redstones can transmit through opaque blocks—but not transparent blocks—he could create a simple binary mechanism by building a system of virtual pistons to manipulate the blocks depending on a "1" or a "0" needs to be transmitted. By stringing enough of them together, like a giant Rube Goldberg machine, he was able to scale it up into a data storage system.

If you want to try it out yourself, Littley has made his "world file" available on Google Drive, though he notes that you'll need to enable experimental versions of the game in order to get the latest update.

Cody Littley

Although you can quibble about the exact definition of a hard drive, as opposed to some other form of persistent storage, you've got to admit that it's impressive. But it's not exactly practical. Because of the difficulty in transferring a file from your hard drive in the game world of Minecraft, you'd actually have to manually enter each byte of data into the drive by hand. And the seek time—the amount of time it takes to find the data that you want to retrieve from the disk—is between six and seven minutes. But that's beside the point. Littley didn't build the drive to be practical.

Littley is a computer science PhD student at University of Texas in Austin, but he says the project had nothing to do with his academic work, which is in distributed computing. "My area of interest is nothing even closely related to hardware," he says. "My background gives me a basic understanding of the topic, but much of what I use to build these things is self taught."

This isn't the first time he has such a contraption in Minecraft. Previously, Littley built a "factory farm" that automatically collects eggs from chickens—"It turned out more gruesome than I expected," he says—and a complex, rail-based messaging system akin to an email server.

The only limit to how complex a system you can build in the game, he says, is that Minecraft won't render things that are too far away from your character within the game. "If I were to build a computer that was a million square miles, the game would pout and refuse to simulate it for me," he says. "Also, the circuitry never really gets smaller, people just build bigger things with it." In other words, Moore's Law doesn't apply to Minecraft.