You beat me to it! I was just going to post about that:I stand corrected! The doors can be configured to teleport you to a single room. (As opposed to the portals, which can contain a list of multiple rooms.) This is pretty cool; when you click on it, it says "a doorway to" (the name of the room you have set it to)", then you simply click "enter". Again, this is one way only, but pretty nice if you like the visual elements of the doors better than the portals. If you own multiple rooms, you could link them to create a walk-through.