Forget World of Warcraft. The new big thing in Internet gaming is Minecraft, a role-playing game with 1980s-era graphics that has become the fastest growing phenomenon on the Web.

Developed by a single over the past year -- Swedish programmer Markus Persson -- Minecraft has nearly one million registered users.

It has no quests. It has no goals, besides avoiding death at the hands of random monsters. It simply presents the player with a wide open sandbox of a world, where they can let their minds run wild.

The premium version, which costs around $14, has so far earned Persson more than $800,000. About $100,000 of that has flooded in over the past 24 hours, according to a message on his website, which claims it is now shifting more than 10,000 paid versions of the game every day.

Minecraft has taken off so quickly that Persson says he is struggling to find time to develop the game while setting up a business and hiring employees.

"Most of my time these days is taken up by meetings and lawyers, accountants, banks, potential partners, potential employees, and the occasional interview," Persson said on his blog last week. "The few hours I do have to develop the game every now and then are mostly spent on looking into bugs and replying to e-mails."

Minecraft's success is all the more remarkable for a game focussed less on pretty graphics or content and more on just letting players build stuff out of blocks.

The deal is, Minecraft is still under development. Pay $14 for it now and you get access to some special features -- like the right to be attacked by monsters -- and you won't have to pay $28 for the official version when -- or if -- it's released.

Or you can simply play it for free and pay full price later.

But what is it?

Minecraft follows in the footsteps of other ultra-niche independent games such as hardcore fantasy simulator Dwarf Fortress, and Persson's own Minecraft prototype, Infiniminer.

If that still means nothing to you -- and that's nothing to be ashamed of -- Minecraft basically allows gamers to build anything at any scale they wish. It's virtual engineering gone mad and the best way to explain it is through videos -- see below.

The other big difference that sets Minecraft apart from other games in the genre is that it actually seems to be able to make money. Lots of money. If you can't believe that, you're not alone. Neither could PayPal, apparently: The company limited Mr Persson's access to his own sales account after the scale of transactions alerted it to what it thought was "suspicious" behavior.

His growing success seems mostly down the the fact that, while the game was originally only known to hardcore PC gamers and niche media, the game has begun to explode across the wider Internet, not least because of a handful of committed users who have shown the capabilities of the game engine to the world.



Here are the five best illustrations of why you too should care about Minecraft:





A Rollercoaster









If you're given blocks to build with, and wide open spaces to build in, making rollercoasters must be near the top of the list. Certainly in was on this guy's to-do sheet, anyway.



Earth









Not 1:1 scale, unfortunately, but still mighty impressive. Having said that, it features proper topography, fantastic detail, and still appreciable size. You can almost see your house from here.



Notre Dame









While it doesn't quite match the Earth for sheer size, there's still something imposing about Notre Dame. Again, attention to detail is fantastic. All it needs is a Quasimodo, and it's set!



A Gigantic 16-Bit Computer









So, someone's built a 16-bit computer in Minecraft. At the moment, all it can really do is count (it's a simple Arithmetic Logic Unit, not a full blown CPU), but even that's impressive. The next few steps? Miniaturization, increasing complexity, and the ability to play Minecraft in the virtual computer. You gotta go all the way down...



The Enterprise





Possibly the most viral of the Minecraft videos, this is exactly what it looks like: a full scale version of the Enterprise, from the TV show Star Trek: The Next Generation. It's obviously not finished, but even this much work clearly took a some time. A similar video can be found here.