I worked for nearly a decade sitting next to these windows. During my former tenure at Brickmania, I always enjoyed seeing the history and marks of time on the old Thorp building. The windows there always stood out to me. Freezing cold in the winter and trying its best not to melt in the summer. Granted, not up to insulation ratings by today's standards, these windows and the building they're part of helped make America.

I've kept the artwork simple enough to work for more modern buildings as well. They'd be a great detail addition for any factory, hanger, or office complex that your Lego City might be building. 

HEADS UP: Even though these are brand new LEGO® elements, they will likely have a few minor scuffs and scratches. They ship loose from Lego and that's the reality of their transparent parts. Personally, I don't notice unless I'm dusting them prior to printing.