All you need is an old window, a high-resolution photo, some foamcore, a staple gun, two eye screws, and chain.
First, I washed the window. Believe me, it was dirty. It had been sitting in our garage for ages. It's one of the only "old" things that was left in this house, so I had to do something with it.
After the bath, I let it dry for a few days. I wanted to be sure all the moisture was out of the wood. Meanwhile, I picked a favorite photo (I took this one last summer of the neighbor cows when DJ and I were on our morning walk). I ordered a poster-sized enlargement from Wallgreens.com.
I glued the poster to a piece of foamcore, and stapled the entire thing to the back of the window. Steve helped me with the eye screws and chain, and here's the result: