I was thinking of car mirrors.
I have a mirror trick of my own.
You know how there is one way mirrors, when used between two rooms they rely on one room being lighter/darker in order to work.
Well if you purchase a special mirror it is possible to make an optical illusion with three rooms in a row involved.
Each of the rooms furthest from each other can see into the interior room, but not into each other. This makes the sense of space much larger. I must talk to a magician or illusionist to see what other ways exist to achieve similar effects.