Killzone 3 is in 3D. Xbox counterpart Halo: Reach is not. But if it was? It'd look a little something like this.
This clip is a fan-made job, taking some of Reach's 3D screenshots (like, the rotating 3D kind) and making them... the other 3D. Like, the "has depth in front of your face" kind. God, this is so confusing.
Whatever, though, if you've got a pair of 3D glasses lying around the house, grab them and give this video a look.
[via Hawty McBloggy]