The NY Times has an article with some interesting facts about mirrors.
Subjects tested in a room with a mirror have been found to work harder, to be more helpful and to be less inclined to cheat, compared with control groups performing the same exercises in nonmirrored settings.
.......people in a room with a mirror were comparatively less likely to judge others based on social stereotypes about, for example, sex, race or religion.
Outline your face on a mirror, and you will find it to be exactly half the size of your real face. Step back as much as you please, and the size of that outlined oval will not change: it will remain half the size of your face (or half the size of whatever part of your body you are looking at), even as the background scene reflected in the mirror steadily changes.