I added a window to mine similar to the one in the video.
I used double sided sticky tape. Turned out real nice. I made a mistake in that I made the window to big which cause the plastic window to get in the say the side panel support and the way it hooks onto the case. I can still get it on, but its not a perfect fit by any means.
Here is what I did for parts.
Plastic window: home depot
U channel molding : advance autoparts.. autozone may have it also
Double sided sticky tape: I got mine at walmart- but homedepot and Advance have it
I used a jig saw with a Lenox bi-metal 24 tooth blade to cut out window. It works, better than a dremal due to speed and control, but I wish there was another way. The rotozip idea sounds interesting. Dremel has a similiar tool as the rotozip.