The roof of the Department of Informatics at the Technische Universität München, mostly made out of glas.
Nice one, reminds me of the good times at TUM. I ask myself how one could improove the blue of the sky in that image not changing the color of the roof using gimp. I tried that in one of my images (not yet posted in the pblog) but I did not manage to alter only the blue not changing the color of things that are not blue... :/ perhups you have an idea?
I didn't manage to make only the sky more blue, but you can use some of the Tools | Color Tools items in Gimp to make the image as a whole more blue...
Tools | Color Tools