Oculus Rift, the virtual realirty gaming headset Pocket-lint encountered at CES in January, has been using a heavily modified version of Half-Life 2 to demonstrate the head and weapon tracking prowess that have recently been added. And developer Nathan Andrews has posted a demo video of the latest version of the system in action.

There are two things to look out for. One - look how responsive the action on screen is in comparison to the movements off. And two, watch out for your lunch, it may end up popping up to say "hello". While the action is totally immersive inside the goggles, it can whip about frenetically outside, making for uncomfortable viewing for some spectators.

"I've added full-head tracking and weapon tracking to Half-Life 2 in preparation for the Oculus Rift dev kit launch," posted Andrews on YouTube. "Once the official Rift APIs are available I'll integrate them, giving people over 70 hours of content [this also works for Episode 1 & 2, the Lost Coast and tons of user generated maps] that they can use to test out their Rift."

Oculus Rift raised the staggering total of $2,437,429 on Kickstarter last year after seeking a tenth of that amount. The virtual reality gaming system is planned for release later this year, with backers originally promised dev kits at the end of 2012. It seems that, although the date has slipped, this video proves that they won't have too long to wait before getting their hands on working samples.