Mapping a room thats bigger inside than outside?

[afi]

I was just thinking... Would it be possible to make a room that's bigger inside than on the outside? Like... you have a small cube with one door on one side. But when you look/go through the door the room is way bigger. Possible? yay or nay

http://youtu.be/VpeA66oUOok?t=27m53s

 

Edit: I just found this.

http://facepunch.com/showthread.php?t=1077425

 

Edit2: This pretty much sums it up, doing it with portals:

http://www.youtube.com/watch?feature=player_embedded&v=2s4ySkR48cI

[spior]

That looks pretty interesting, but I don't think it'll be as smooth in JKA

@ bumping for portalmod

[mrwonko]

Yeah, that's totally possible... in Prey.

[Szico VII]

Could cheat it and have the door as a camera portal (looking exactly where the normal door looks) which teleports the player to a physically bigger room (which is actually elsewhere on the map)

Would have to remove teleporter effect for best transition.

[Astral Serpent]

It is possible but you'll need new entities or something for a seamless portal, Raz0r has/is worked/ing on one for QtZ.