I thought I had responded to using old windows in the Garden - but I'll try one more time.
There are three gardens - mine included that have used windows in the garden. Here is a picture of mine
the next is a garden that was seen in the 2008 AHS National here in Houston. This garden belongs to Boone Keeling. Great idea about using windows
the last picture belongs to the garden of Mike & Susan Peppers also in the Houston area. Sorta a play on Boone's display