This is pretty awesome. It'll definitely be a great multiplayer experience.
Portal via Joystiq
Imagine fighting one of your mates on this. You fire the 'exit' portal to a wall - which descends into a pit / trench. And fire the 'entry' portal, on the floor, where one of your mates runs over unexpectedly. ROFL.
I think they've kinda took the idea from the developers of
Prey. But nonetheless, it seems like a great gameplay experience.