We carefully removed the mirror from the too large frame, applied construction adhesive to the back, and stuck it right on the wall over our bathroom vanity. As I said in this post, we had someone cut leftover door and window trim to fit around the mirror at a cost of $20. A nice custom mirror for $120. Not too shabby.
Here's the finished product.
We were left with a perfectly good 70"x50" black frame. We decided to hang the frame in our mudroom. I painted inside the frame with magnetic paint and then chalkboard paint. It makes a great place to display the kids' artwork and write messages.
This is how it turned out.
If you have some old items sitting around collecting dust and you think there's no use for, e-mail me a picture. I'm sure I can help you come up with some way to repurpose it.