While you’ve been hearing about virtual reality for the last 20 years or so, today the hardware required to build such a rig is finally to the point where it’s within the reach of consumers. As seen here, Relativty is a SteamVR-compatible headset that can be made for around $100.
Relativty uses a 3D-printed frame to house its 2560 x 1440 LCD screen, along with a pair of 80mm Fresnel lenses to properly focus the image. Control is accomplished via an Arduino Due and an MPU-6050 accelerometer, which feeds head-tracking info to an external gaming system.
At this point, the device is clean though fairly basic, and will hopefully be the start of a truly excellent open source project as features are added.