There is nothing quite like having John Carmack tell you about a technological breakthrough that excited him.

The id Software programming genius who co-created Doom and launches rockets in his spare time will just unload on you. And—this is flattering—he will assume you can keep up.

Yesterday at E3 in Los Angeles, I pretty much just asked Carmack to explain why he's programming the re-release of Doom 3 to work with a prototype $500 head-mounted display. His response was pure Carmack, a dozen-minute nearly uninterrupted oral dissertation on the ins and outs of head-mounted tech.

John Carmack is more excited about a future with immersive virtual reality gaming than he is one with everyone wearing augmented reality Google glasses. Watch the video to find out why. Or, hell, just watch the video you and you'll understand why there's no one in the world quite like John Carmack.

(Note: We've trimmed the part of the video that involved me playing Doom 3 with the headset, since that's no fun for you to watch. It was very cool for me to see, but that can't come through unless you're wearing the goggles. What can come through in this video is Carmack. We're barely editing him here at all.)