One for tech geeks, this. Guerrilla released on PSN a playable version of the 'Killzone in 4-D' tech demo, apparently used in a US TV commercial (featured below) to show off the game's impressive visuals.
The download, now entitled Behind the Bullet, gives you "an inside look at the making of the commercial, enabling you to take control and slow down the action, move the camera axis and pivot, hear audio commentary from multiple selectable sources such as the art director or technical director at Guerrilla Games."
And if you're a real geek, you can fiddle with "a variety of buffers and filters to see how every single frame of the commercial was created using the game engine technology," explains Sony. Screens of it in action are below.