Feng Shui | Mirrors
Mirrors have been called the "aspirin" of Feng Shui; If you have any sort of grievance or discomfort, throw one up and it can't hurt. However, it's not quite that simple. There are some do's and don't's when it comes to mirror placement.
Primarily, mirrors are going to multiple whatever they reflect. Therefore, they should be reflecting something you like and something you want more of - flowers, an outdoor view, a comfortable chair. Just make sure that in the mirror's reflection you can't also catch a glimpse of your closet that hasn't been cleaned out in years.
Mirrors also should not be used in the bedroom, or at the very least should not face the bed. If someone has trouble sleeping and has a mirror in their bedroom, covering it up to see if it makes a difference could be a good place to start.
One is also advised not to use mirrors with any sort of distortion (i.e. an antiqued finish or a convex shape). Don't know how ardently I would follow this rule in my own life because I do love antiqued mirrors.
As with anything in Feng Shui, mirror placement is both simple and complicated. For more in depth reading on mirrors, click here.