If you don't mind to waste a few minutes, try this: Make a QR code (based on any text. This is the result of my name) using whatever program you have (I use QtQR). Substract the white color areas (Photoshop or Gimp) and save the image as .png. Import this image to Corel Draw (I use Inkscape) and vectorize it, saving it as .svg. Import this to Blender, convert to objet from curve, extrude and make some holes to the mesh (as if they were windows), apply the modifier array to add as many flats as you want and that's it. Yo can adjust the size of the individual buildings to improve the scene. You don't really need to download this blend. Have fun.
It's quite a good idea, and if you are using Windows there's another free application, Zintportable, that lets you export the QR directly as .svg. Once you have imported it in Blender, you just have to delete the square surrounding the curves of the QR code.
What a wonderful idea!