I bought an old crumbly, dirty window from a girl. She had bought a load of 50 (!!) of them from some Amish people in Pennsylvania, and only needed 2, so she sold the rest off. I bought two from her, not really knowing what to do with them, but thinking they could be very cool.
So I decided to make one into a chalk board to hang in my kitchen--something to write lists on, or notes, or reminders, or draw pictures. So here's what I did...
Here's the window (this is actually the other window, but I didn't photo the chalkboard window before I began painting)
I bought some chalk board paint from the craft store. $7, but you can probably find it cheaper (the red, green, brown, and other colors were $3.50).
Next, put on the "D rings".
I hang paintings for a living (if you can call it that), so I am quite familiar with the ins and outs of hanging paintings/stuff on walls. These principles apply to most anything you hang on your wall. Buy "D rings" from the craft/hardware store. For something heavy, like this window, (probably 10-15 lbs), I like something relatively heavy duty--meaning you want the screws to be substantial. You don't want screws to rip out of the wood because they're too wimpy to hold your heavy thing. Better too much than too little, in this case.