A Friend/neighbor of mine has a very large empty wall and vaulted ceilings. She had the idea of placing a large mirror on the wall to break things up and add dimension and interest. I found a variety of examples of large mirrors used for this same reason. And although these might not be her exact style they will hopefully serve for some inspiration.

Below I have listed a number of blogs and websites on tutorials for how to frame out large mirrors. This way you can get the exact look you want, for less!
Framing an old mirror D.I.Y instructions:

sturdy, more time consuming DIY instructions here

simple DIY instructions here

intricate design DIY instructions here

a bathroom mirror DIY, but same concept here

mosaic type frame here

very embellished mirror here