So, I'm just going to suggest a circumstance, and leave it up for discussion. I recently read an interesting forum on super reflective material in which all energy is reflected (all theoretical, of course) and none of it is absorbed by the material. Now, say we construct a one way mirror where the other side acts as a window like in interrogation rooms. What would it look like from an observer's standpoint at different positions and with or without sources of light on either side of the material. Have at it!