Virtual Reality has been one of those science fiction technologies we've been promised for decades. But while jetpacks and moon colonies are still a ways off, affordable and effective VR technology is available now, for both fun and educational purposes. If you have a smartphone, you can try out some basic VR applications for little or no extra money, and if you really want to dive in, there are even more options at your (virtual) fingertips.

Enter a virtual world using...cardboard?
When you think virtual reality, you probably think of the latest and greatest, cutting edge technology. But if you already have a smartphone, you can experience virtual reality with just a cleverly folded piece of cardboard. Google took the VR world by surprise in 2014 with their Cardboard Viewer, which allows you to insert a smartphone into a glasses-shaped cardboard viewer and look through stereoscopic lenses for a simple but effective VR experience. You can buy a variety of viewers directly from Google's website, or from a variety of third-party online vendors. Since phone sizes vary, make sure the viewer you purchase is compatible with your device.

Level up with a smartphone
If you've tried Cardboard and liked it, there are more feature-packed (and ergonomic) headsets in the $80-100 range like Daydream View, also from Google and Gear VR. These usually come with headbands, eye shields and some sort of fabric covering for a more immersive and comfortable experience. Many VR headsets also include a handheld controller, which will allow you to partake in the rapidly growing world of VR gaming. VR headsets are usually only compatible with a very specific make or model of smartphone, so do your research before you make the plunge. You can get a good overview of current options at The Wirecutter.

Go all in with PC or console add-ons
The most robust, advanced VR experience requires a current-generation PC or gaming console and a larger headset/controller rig. These hardware options allow you to experience top-of-the-line gaming and immersive virtual worlds. They'll also set you back anywhere from $500-$1,000, plus the cost of a computer or game console. Oculus Rift, recently acquired by Facebook, and the HTC Vive are both designed for use with a personal computer, while the less expensive PlayStation VR connects to a PlayStation 4.

There's no question that Virtual Reality has a long way to go before it reaches the ubiquity and usefulness of personal computers and smartphones. But for the adventurous gamer or early tech adopter, the promise of new virtual worlds to explore is an exciting one. Happy exploring!