State Bank

category:national projects
It is as cheap as the Colossus Wonder, and can be built quickly, and is meant to raise your Pop Cap and your Wealth caps. However it also functions as an early warning system, capable of spotting enemy units at a distance (but not stealthed ones). 
LOS of this building is further enhanced by your Science research which increases its LOS by a whopping 10 per research level. However, if it is destroyed, it produces a lot of Wealth for the enemy (unless you are playing as Russia, or have obtained their national powers for your own use).