Forget Android L, Android Wear, AndroidOne and every other new “android” variant Sundar Pichai stumbled through during Google’s 3-hour keynote. The coolest thing coming out of Google I/O wasn’t new software and thousands of APIs, it’s a small DYI VR headset that anyone can make.

After today’s keynote Google I/O attendees were given a taste of Google’s next wearable product that’s made from nothing more than cardboard. The experimental VR toolkit sounds like another one of Google’s April Fool’s jokes, except it’s totally real, and even if you didn’t happen to pick up a free one from Moscone West, you can build your own at home.

Facebook spent billions acquiring Occulus for its immersive virtual-reality headsets, but Google is taking the ultimate low-tech route with the Cardboard headset that uses your smartphone and some lenses to give users a demo of the impending VR-revolution.

Google already has a number of immersive demos you can try on Android to get inspired, including the following:

• Earth: Fly where your fancy takes you on Google Earth.
• Tour Guide: Visit Versailles with a local guide.
• YouTube: Watch popular YouTube videos on a massive screen.
• Exhibit: Examine cultural artifacts from every angle.
• Photo Sphere: Look around the photo spheres you’ve captured.
• Street Vue: Drive through Paris on a summer day.
• Windy Day: Follow the story (and the hat) in this interactive animated short from Spotlight Stories.

Cardboard was born as a 20% project by David Coz and Damien at Google’s Cultural Institute in Paris. Apparently the homegrown VR-headset inspired enough enthusiasm from other Googlers that an experimental SDK was churned out by a larger group in time for I/O.

To learn how to make your own Cardboard viewer at home, order up an extra-large pizza and grab the Cardboard design files from Google’s site. You can grab the free Cardboard app from Google Play right now.