I started work on producing Sci-Fi buildings to go with 15mm figures. The intention is to eventually be able to stage city fights. I went with a flat roof for ease of positioning figures and the concept of the initial building is a small prefabricated concrete dwelling.
It was made from plastic card with cocktail stick piping and Green Stuff used for the utility box on the side of the building and for the curve in the water pipes to the roof.
I need to make a lot more building types to complete this project, but it's a good start I think. :)