Google Cardboard puts virtual reality in everyone's reach

It's not often that you can get a truly breathtaking technological innovation for the cost of a few dollars in cardboard and a magnet. But that's what Google (GOOG) has recently managed to pull off with its aptly named Google Cardboard.

At the recent Google I/O, the search company's annual tech summit, attendees were handed a curious Viewmaster-like visor made almost entirely of cardboard, scored and folded together like an origami version of virtual reality gadget Oculus Rift. And indeed, that's exactly what the goal of this project was intended to be: A low-tech version of the Kickstarter-funded VR headset.

By way of comparison, Oculus Rift headsets, still only available to developers, sell for about $350 each and provide a high-fidelity, immersive 3D experience complete with head tracking, so you can spin around and see a scene from any vantage point as if you were really there. Oculus Rift headsets tether you to a PC, however, so you can't walk around; you need to use a controller to move forward and backwards. This technology has certainly gotten a lot of industry attention, with Facebook recently buying the company for $2 billion.

So what can a dollar's worth of cardboard accomplish? Quite a bit, actually. When you insert an Android phone running the Google Cardboard app, you get a split screen view that combines into a 3D image. There's a clever sliding button on the side that mimics a screen tap to make selections. (The magnet stays affixed to the side of the visor thanks to a metal disk that's glued on the insider of the device.) Google supplies a small handful of demo experiences in the app: You can swoop and fly through Google Earth, for example, starting in space and maneuvering all the way to ground level. You go wherever you orient yourself, because the phone tracks your head movements. There's also a charming, animated movie called "Windy Day"that requires you to twist your head to follow the 360-degree action. Amid a handful of other apps, you can also watch YouTube videos as if they're on a giant drive-in screen.

But there's a lot more than that, since Google Cardboard isn't limited to working with just software written by Google. The Google Play store has a wide variety of 3D-ready apps that you can load into a Cardboard headset -- a simple search for "VR" turns up a number of options. Two of the best: Tuscany Drive, a cool interactive demo that lets you wander an Italian seaside resort in full 3D, and SpaceTerrorVR, a 3D horror game set on a space station.

If you weren't at Google IO, don't worry: You can get your very own pair of Google Cardboard quite easily. You can build one yourself from the official plans, or you can buy one pre-assembled for as little as $20 from a site like Unofficial Cardboard. Just make sure you have a supported Android handset before you cut up a pizza box or order a completed visor -- most do, but you need at least Android 4.1.

So what's the point of all this? Right now, it's simply a lot of fun,. You'll stand with your mouth agape the first time you watch the movie or fly around Google Earth with Cardboard. But if anything, Google is demonstrating that Facebook and Oculus Rift are right: Immersive 3D virtual reality truly is on the way.