I give myself an erection, the sheer size of which mere walls are unable to contain. The resulting explosion of construction materials levels a small city.
If I can tell the room is white there has to be light coming from somewhere.
Also, Unless my captors want me to die in a shot while, there will be a source of air.
Search the room
and already taken, but
XYZZY
Brian
Well, I guess I would wait for the room to move in sync with all the other square rooms around me and for all of the other people in the same situation in other rooms to wander into mine so that we can brainstorm a way out like they did in the movie Cube. If that didnt happen in about half an hour, I would walk to a corner and place one foot in front of the other until I covered the entire floor of the room to search for secret doors or windows. Then, assuming that didnt work, I move onto the walls and feel every inch for possible exits. This last bit is a last ditch effort though as I am short and would probably only have access to the lower 2/3 of the wall. If the way out is in the ceiling I am fucked unless it is a very small room.
I’d just do what I always do anyway: masturbate. I don’t need to leave the room to do that. In fact, it would have plenty of privacy so it would be perfect.
If there’s no door, then I’ll just go through the empty doorway.
I bet your still a virgin.
I’ll cancel my intended answer and just curse the noseless astronomer with the fury of a thousand supernovae. 
I’ve just seen a much better thread where we were asked **our reactions ** to this situation. The answers were supposed to show what you thought of death.
But this version seems pretty pointless, given that humour doesn’t ‘solve’ it.
I’ve seen this before as:
I woke up to find myself in a room with no doors and no windows. The walls were completely solid. A mirror and a desk were in the room with me. How did I get out?
I looked in the mirror to see what I saw. I took the saw and cut the desk in half. I put the two halves together again to make a whole. I took the hole and put it on the wall and then walked through.
In fact, it was this thread that inspired me to start that one.
I looked to my right and saw a wall. I looked to my left and saw another wall. I now had two saws. I used one saw to cut the other saw in half. I put the two halfs together and made a whole. I escaped by crawling out the hole.
I run around in circles until I’m worn out.
I think, therefore I am.
I think of a door, therefore, it is.
I go through the door.
Buh-Bye.
I search for some means of exit; I find none. I yell for someone to let me out; no one does. After five miserable days I die of thirst.
And because I didn’t get the point of the koan, I’m reincarnated as a rock.
Whereupon you have democracy <jubilant>thrust!</jubilant> upon you.
I pretend that I am an economist. I need a door, therefore I assume there is a door. I exit via the door.
sinjin
Once you’re out of the room, you find yourself in a hallway carved out of rock. At either end of the hallway is a door. One says Simplicity. The other says Complexity.
Pick one.
No.
So how did we get out of the room?
As for the doors, I prefer a balanced mathematical approach. Does this make me mean?
Do you know any interesting games?
I’m not sure where Simpli City is, but maybe I can phone home from there.
One.
waits
Now what?