Over at the Centives economic blog, they figured out how much it would cost to build the Death Star in 2012 dollars. Spoiler: A lot. It would cost a lot.
We began by looking at how big the Death Star is. The first one is reported to be 140km in diameter and it sure looks like it’s made of steel. But how much steel? We decided to model the Death Star as having a similar density in steel as a modern warship. After all, they’re both essentially floating weapons platforms so that seems reasonable.