I had a customer a few years ago with similar issue with a German shepherd pup. After finding out that the pup had to be crated for a few hours during the day, I tried to help them out with a better solution than a crate for a few hours during the day.
Well, It was pretty easy for me to figure out, Since these people had a 2 story home and under the stairwell was a large storage closet.
What I did was remove the door and cut it in half, Then I added a top ledge to the door and later on added a little window in the middle of the bottom section of the door.
Here's a picture prior to the top ledge and the window. I never did take final completed pictures. But it turned out nice and everyone was pleased with the final results.
The room itself was rather large even though in the pictures it seems small.
http://i41.tinypic.com/b6dmkk.jpg http://i41.tinypic.com/i4mis1.jpg